Introduction. The structure of the mark schemes

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2 2007 KS3 Mathematics test mark scheme: Paper 1 Introduction Introduction The test papers will be marked by external markers. The markers will follow the mark scheme in this booklet, which is provided here to infm teachers. This booklet contains the mark scheme f paper 1 at all tiers. The paper 2 mark scheme is printed in a separate booklet. Questions have been given names so that each one has a unique identifier irrespective of tier. The structure of the mark schemes The marking infmation f questions is set out in the fm of tables, which start on page 11 of this booklet. The columns on the left-hand side of each table provide a quick reference to the tier, question number, question part and the total number of marks available f that question part. The Crect response column usually includes two types of infmation: a statement of the requirements f the award of each mark, with an indication of whether credit can be given f crect wking, and whether the marks are independent cumulative examples of some different types of crect response, including the most common. The Additional guidance column indicates alternative acceptable responses, and provides details of specific types of response that are unacceptable. Other guidance, such as when follow through is allowed, is provided as necessary. Questions with a UAM element are identified in the mark scheme by an encircled U with a number that indicates the significance of using and applying mathematics in answering the question. The U number can be any whole number from 1 to the number of marks in the question. F graphical and diagrammatic responses, including those in which judgements on accuracy are required, marking overlays have been provided as the centre pages of this booklet. The 2007 key stage 3 mathematics tests and mark schemes were developed by the Test Development team at Edexcel. 2

3 2007 KS3 Mathematics test mark scheme: Paper 1 General guidance General guidance Using the mark schemes Answers that are numerically equivalent algebraically equivalent are acceptable unless the mark scheme states otherwise. In der to ensure consistency of marking, the most frequent procedural queries are listed on the following two pages with the prescribed crect action. This is followed by further guidance relating specifically to the marking of questions that involve money, native numbers, algebra, time, codinates probability. Unless otherwise specified in the mark scheme, markers should apply the following guidelines in all cases. 3

4 2007 KS3 Mathematics test mark scheme: Paper 1 General guidance What if The pupil s response does not match closely any of the examples given. The pupil has responded in a non-standard way. The pupil has made a conceptual err. The pupil s accuracy is marginal accding to the overlay provided. The pupil s answer crectly follows through from earlier increct wk. There appears to be a misreading affecting the wking. The crect answer is in the wrong place. Markers should use their judgement in deciding whether the response cresponds with the statement of requirements given in the Crect response column. Refer also to the Additional guidance. Calculations, fmulae and written responses do not have to be set out in any particular fmat. Pupils may provide evidence in any fm as long as its meaning can be understood. Diagrams, symbols wds are acceptable f explanations f indicating a response. Any crect method of setting out wking, however idiosyncratic, is acceptable. Provided there is no ambiguity, condone the continental practice of using a comma f a decimal point. In some questions, a method mark is available provided the pupil has made a computational, rather than conceptual, err. A computational err is a slip such as writing 4 6 = 18 in an otherwise crect long multiplication. A conceptual err is a me serious misunderstanding of the relevant mathematics; when such an err is seen no method marks may be awarded. Examples of conceptual errs are: misunderstanding of place value, such as multiplying by 2 rather than 20 when calculating 35 27; subtracting the smaller value from the larger in calculations such as to give the answer 21; increct signs when wking with native numbers. Overlays can never be 100% accurate. However, provided the answer is within, touches, the boundaries given, the mark(s) should be awarded. Follow through marks may be awarded only when specifically stated in the mark scheme, but should not be allowed if the difficulty level of the question has been lowered. Either the crect response an acceptable follow through response should be marked as crect. This is when the pupil misreads the infmation given in the question and uses different infmation. If the iginal intention difficulty level of the question is not reduced, deduct one mark only. If the iginal intention difficulty level is reduced, do not award any marks f the question part. Where a pupil has shown understanding of the question, the mark(s) should be given. In particular, where a wd number response is expected, a pupil may meet the requirement by annotating a graph labelling a diagram elsewhere in the question. 4

5 2007 KS3 Mathematics test mark scheme: Paper 1 General guidance What if The final answer is wrong but the crect answer is shown in the wking. Where appropriate, detailed guidance will be given in the mark scheme and must be adhered to. If no guidance is given, markers will need to examine each case to decide whether: the increct answer is due to a transcription err If so, award the mark. in questions not testing accuracy, the crect answer has been given but then rounded truncated the pupil has continued to give redundant extra wking which does not contradict wk already done the pupil has continued, in the same part of the question, to give redundant extra wking which does contradict wk already done. If so, award the mark. If so, award the mark. If so, do not award the mark. Where a question part carries me than one mark, only the final mark should be withheld. The pupil s answer is crect but the wrong wking is seen. The crect response has been crossed rubbed out and not replaced. Me than one answer is given. The answer is crect but, in a later part of the question, the pupil has contradicted this response. A crect response should always be marked as crect unless the mark scheme states otherwise. Mark, accding to the mark scheme, any lible crossed rubbed out wk that has not been replaced. If all answers given are crect a range of answers is given, all of which are crect, the mark should be awarded unless prohibited by the mark scheme. If both crect and increct responses are given, no mark should be awarded. A mark given f one part should not be disallowed f wking answers given in a different part, unless the mark scheme specifically states otherwise. 5

6 2007 KS3 Mathematics test mark scheme: Paper 1 General guidance Marking specific types of question Responses involving money F example: Accept Do not accept Any unambiguous indication of the crect amount 3.20(p), 3 20, 3,20, 3 pounds 20, 3-20, 3 20 pence, 3:20, 7.00 The unit, p, is usually printed in the answer space. Where the pupil writes an answer outside the answer space with no units, accept responses that are unambiguous when considered alongside the given units with given in the answer space, accept Given units amended with crossed out in the answer space, accept 320p 700p Increct ambiguous indication of the amount 320, 320p 700p Ambiguous use of units outside the answer space with given in the answer space, do not accept 3.20p outside the answer space Increct placement of decimal points, spaces, etc increct use omission of 0 3.2, 3 200, 32 0, Responses involving native numbers F example: 2 Accept Do not accept To avoid penalising the err below me than once within each question, do not award the mark f the first occurrence of the err within each question. Where a question part carries me than one mark, only the final mark should be withheld. Increct notation 2 6

7 2007 KS3 Mathematics test mark scheme: Paper 1 General guidance Responses involving the use of algebra F example: 2 + n n + 2 2n n n 2 2 Accept Take care! Do not accept Unambiguous use of a different case variable N used f n x used f n! Unconventional notation n 2 2 n n2 n + n f 2n n n f n 2 n 2 f n n 2 + 1n f 2 + n 2 + 0n f 2 Within a question that demands simplification, do not accept as part of a final answer involving algebra. Accept within a method when awarding partial credit, within an explanation general wking. Embedded values given when solving equations in solving 3x + 2 = 32, = 32 f x = 10 To avoid penalising the two types of err below me than once within each question, do not award the mark f the first occurrence of each type within each question. Where a question part carries me than one mark, only the final mark should be withheld. Wds used to precede follow equations expressions t = n + 2 tiles tiles = t = n + 2 f t = n + 2 Unambiguous letters used to indicate expressions t = n + 2 f n + 2! Wds units used within equations expressions n tiles + 2 n cm + 2 Do not accept on their own. Igne if accompanying an acceptable response. Ambiguous letters used to indicate expressions n = n + 2 f n + 2 7

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9 2007 KS3 Mathematics test mark scheme: Paper 1 General guidance Responses involving probability A numerical probability should be expressed as a decimal, fraction percentage only. F example: % 10 Accept Take care! Do not accept Equivalent decimals, fractions and percentages 0.700, , 35 50, 70.0% A probability crectly expressed in one acceptable fm which is then increctly converted, but is still less than 1 and greater than = The first four caties of err below should be igned if accompanied by an acceptable response, but should not be accepted on their own. However, to avoid penalising the first three types of err below me than once within each question, do not award the mark f the first occurrence of each type of err unaccompanied by an acceptable response. Where a question part carries me than one mark, only the final mark should be withheld.! A probability that is increctly expressed 7 in 10 7 over 10 7 out of 10 7 from 10! A probability expressed as a percentage without a percentage sign.! A fraction with other than inters in the numerat and/ denominat.! A probability expressed as a ratio 7 : 10, 7 : 3, 7 to 10 A probability greater than 1 less than 0 9

10 2007 KS3 Mathematics test mark scheme: Paper 1 General guidance Recding marks awarded on the test paper All questions, even those not attempted by the pupil, will be marked, with a 1 a 0 entered in each marking space. Where 2m can be split into gained and lost, with no explicit der, then this will be recded by the marker as 1 0 The total marks awarded f a double page will be written in the box at the bottom of the right-hand page, and the total number of marks obtained on the paper will be recded on the front of the test paper. A total of 120 marks is available in each of tiers 3 5, 4 6, 5 7 and 6 8. Awarding levels The sum of the marks gained on paper 1, paper 2 and the mental mathematics paper determines the level awarded. Level threshold tables, which show the mark ranges f the award of different levels, will be available on the NAA website from Monday 25 June QCA will also send a copy to each school in July. Schools will be notified of pupils results by means of a marksheet, which will be returned to schools by the external marking agency with the pupils marked scripts. The marksheet will include pupils sces on the test papers and the levels awarded. 10

11 2007 KS3 Mathematics test mark scheme: Paper 1 Tier 3 5 only 1 Crect response Additional guidance Euros

12 2007 KS3 Mathematics test mark scheme: Paper 1 Tier 3 5 only 2 Crect response Additional guidance Number line 2m Gives all three crect values in the crect positions, ie Gives at least two crect values in the crect positions! F, follow through Accept as their previous increct value 3, provided their previous increct value < 3, f accept 1 3 (err) 6 2 (err) times table 3 Crect response Additional guidance 36 5 U

13 2007 KS3 Mathematics test mark scheme: Paper 1 Tier 3 5 only Feeding times 4 Crect response Additional guidance a 12:35(pm)! Throughout the question, omission of pm Condone, f part (a) accept 12:35 Throughout the question, increct times, f part (a) 12:35am b Tigers Unambiguous indication T c 30 d Gives three crect times, ie Use of the 24 hour clock Elephants at Otters at Seals at 2:15(pm) 1:00(pm) 4:00(pm) U1 Elephants at Otters at Seals at 3:20(pm) 1:00(pm) 4:00(pm) 5 Crect response Additional guidance 121 Wk out 7 13

14 2007 KS3 Mathematics test mark scheme: Paper 1 Tier 3 5 only 6 Crect response Additional guidance a 12 Dollars b 5 c 40 7 Crect response Additional guidance a Indicates only 15, 20 and 30, ie Divisibility b Indicates only 12, 15 and 30, ie c Indicates only 15 and 30, ie! Follow through F part (c), accept follow through as all values indicated that were also indicated in both parts (a) and (b), provided this is not all none of the boxes 14

15 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 3 5, Crect response Additional guidance a a Harrogate Unambiguous indication, f part (a) H Populations b b 2m Completes all three of the sentences crectly, ie Ash Vale London 100 Completes two of the sentences crectly 15

16 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 3 5, 4 6 Number grids 9 2 Crect response Additional guidance 3m Completes all three grids crectly, ie m Completes the first two grids crectly Completes the third grid crectly and gives any two crect entries in the first two grids Completes the third grid crectly, gives any one crect entry in the first grid, makes an err in the right hand entry of the second grid, but follows through crectly to give their product Gives any two crect entries in the first two grids Completes the third grid crectly U1 Gives any one crect entry in the first grid, makes an err in the right hand entry of the second grid, but follows through crectly to give their product 16

17 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 3 5, Crect response Additional guidance a a Gives a value greater than 62.5, but less than 63.5 Babies Gives a value greater than 52.5, but less than 53.5! The two values in part (a) transposed but otherwise crect Mark as 0, 1 b b Indicates the crect point at (34, 72)! Inaccurate indication Accept any unambiguous indication within 2mm of the crect intersection of the grid Cards f fractions 11 4 Crect response Additional guidance a a Gives either b b Gives a crect fraction between 1 and 1, ie 2 4 6, 6 8, 6 10, 8 10,

18 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 3 5, 4 6 Pentagon perimeter 12 5 Crect response Additional guidance Shows implies that the length of one side is 5.4cm 0.2cm seen 54 2 seen Answer of 26, 26.5, 27, with no evidence of increct wking Answer of 260, 265, 270, with no evidence of increct wking Markers may find the following values useful: Side length Perimeter F the first mark, me than one value f the side length is given Shows implies a crect method f finding their perimeter Intention to multiply their side length by 5 Intention to add all 5 of their side lengths Answer of 26, 26.5, 27, with no evidence of increct wking Answer of 260, 265, 270, with no evidence of increct wking 5.4 seen, answer of (err) 5.4 seen, answer of 45 (err) 5 (err) seen, answer of 25 F the second mark, follow through from their side length(s) F the second mark, response does not show imply an unambiguous clear method f finding their perimeter Gives the crect value f their perimeter Answer of 26, 26.5, 27, with no evidence of increct wking Answer of 260, 265, 270, with units amended to mm, and no evidence of increct wking! F the third mark, follow through from their side length(s) Accept follow through provided their calculation involves bridging the units, from a side length of 5.7 accept 28.5, from a side length of 5.1 do not accept

19 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 3 5, 4 6 Multiple and fact 13 6 Crect response Additional guidance a a Gives two different 3-digit multiples of b b Gives a 2-digit fact of 100, ie 10, 20, Gives a different 2-digit fact of 100 from any credited f the first mark of part (b)! Facts of 100 given that do not have 2 digits, f both marks in part (b) Mark as 0, 1! 2-digit facts of 100 given within fact pairs, f both marks in part (b) Mark as 0, 1 Native facts Same number 14 7 Crect response Additional guidance a a 7.5 Equivalent fractions and decimals b b Gives the value 1.5 in each of the three boxes 19

20 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 3 5, 4 6, Crect response Additional guidance Squares Indicates No and gives a crect explanation A rectangle is four-sided and also has four right angles Minimally acceptable explanation Rectangle! Response names rectangles, but also implies there are other examples Condone provided there are no other increct examples named, accept Many shapes have four right angles, f example a rectangle, do not accept A rhombus and a rectangle must have four right angles U1 Incomplete explanation There is another four-sided shape with four right angles Crect response Additional guidance x = 8 a a a Indicates only 40, ie b b b Indicates only 16, ie c c c Indicates only 64, ie 20

21 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 3 5, 4 6, Crect response Additional guidance Grid 3m Gives all six crect values in the table, then gives the crect answer to the multiplication, ie Answer: m Gives at least four crect values in the table, even if the answer to the multiplication is increct omitted Gives at least three crect values in the table, then follows through to add crectly their six values that would give the answer to the multiplication Gives the answer to the multiplication as 5148, even if the grid has not been used has increct entries Gives at least three crect values in the table, even if the answer to the multiplication is increct omitted U1 Gives at least two crect values in the table, then follows through to add crectly their six values that would give the answer to the multiplication 21

22 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 3 5, 4 6, Crect response Additional guidance a a a 1 equivalent probability 20 Sweets b b b Indicates green Unambiguous indication of colour G Completing calculations Crect response Additional guidance Gives any two values that add to give Fractions, decimals natives Given operation changed, f the first mark 0 8 Gives any two values that subtract to give 8, in the crect der

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24 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 3 5, 4 6, 5 7 Positive and native Crect response Additional guidance a a a 18 b b b 2 c c c Indicates the equation y = x 2, ie Crect response Additional guidance Barrels 2m Gives all three crect fractions in their simplest fm, ie Equivalent decimals Gives any two crect fractions in their simplest fm Shows a crect first step of simplification f all three crect fractions, even if there is increct subsequent simplification ! F, follow through Accept their third fraction as their second fraction 2, provided all three fractions are given in their simplest fm, f accept (err)

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27 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 4 6, 5 7, 6 8 Counter probabilities Crect response Additional guidance a a a 2m Completes the table with the three crect values in the crect positions, ie Colour of counters Number of counters Red 6 Blue 3 Green 6 Probability Equivalent probabilities Increct notation U1 Gives at least one crect value in the crect position b b b Indicates that the probability has decreased, ie U1 27

28 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 4 6, 5 7, 6 8 Three straight lines Crect response Additional guidance Gives a = 50 and gives a crect reason Angle a is on a straight line with 130, so a = a is supplementary with 130, so a = 180 The angle vertically opposite 130 is 130, 360 ( ) = 100, (angles at a point) a is 100 = 50 (also vertically opposite) 2 Minimally acceptable reason On a straight line Supplementary Opposite angles and angles at a point Infmal reason without the crect geometrical property identified U1 Incomplete reason It is adjacent to the 130 angle Gives b = 60 and gives a crect reason Angle b is vertically opposite the 60 angle, so it is also 60 The angle on a straight line with b is 120, so b is (angles at a point) Minimally acceptable reason Opposite Angles on a straight line and angles at a point Infmal reason without the crect geometrical property identified b is equal to the 60 angle next to it U1 Incomplete reason It is the same as the 60 angle 28

29 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 4 6, 5 7, 6 8 Three straight lines (cont) Crect response Additional guidance Gives c = 70 and gives a crect reason There are 180 in a triangle, so c = The exteri angle of a triangle is equal to the sum of the two opposite interi angles, so c = Minimally acceptable reason Angles in a triangle Exteri angle = sum of two opposite interi angles We ve already got 50 and 60 in the triangle! Follow through Accept as 180 (their a + b), alongside a crect reason referring to angles in a triangle, as 130 their b alongside a crect reason referring to an exteri angle of a triangle Infmal reason without the crect geometrical property identified 180 (a + b) 130 b U1 Incomplete reason It is in a triangle All the inside angles add up to

30 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 4 6, 5 7, Crect response Additional guidance a a a Indicates 1 10 and 1 100, ie Ninths b b b Indicates 11%, ie c c c 2 9 Equivalent fractions Equivalent decimals percentages Increct notation Crect response Additional guidance 2m 1 equivalent 2 Equation Shows implies a crect first step of algebraic manipulation that removes the brackets 2 2n = 12 4n + 10 = 12 2n + 5 = 6 4n = 2 2n =

31 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 4 6, 5 7, 6 8 Circle wking Crect response Additional guidance Gives a crect explanation The most common crect explanations: Show the crect wking It should be 16 not 8 Needs to be radius 2, not diameter Minimally acceptable explanation r 2 r 2 Incomplete explanation The 8 is wrong Address the misconception He is finding the circumference not the area He is using 2 r, not r 2 He has done 4 2 instead of 4 2 Minimally acceptable explanation Circumference It s not 2 r [ d] He didn t square the 4 He didn t square the radius! Use of perimeter f circumference Condone Incomplete explanation He used the wrong fmula He used the diameter He hasn t used the radius He doubled the radius Show that his wking gives an increct answer He gets 25.( ), but it should be 50.( ) His answer is half as big as it should be Minimally acceptable explanation 50, not 25 It should be his answer 2 U1 Incomplete explanation 50 His answer is too small 31

32 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 4 6, 5 7, 6 8 Thinking fractions Crect response Additional guidance Crect response Additional guidance Cube a 54x 2 Unsimplified expression unconventional notation 9x 2 6 9x 2 + 9x 2 + 9x 2 + 9x 2 + 9x 2 + 9x 2 54xx b 2m Gives a crect, simplified expression, ie 27x 3 (3x) 3! Unsimplified expression unconventional notation 3 3 x 3 27 x x x F 2m, do not accept F, condone Shows implies a crect method f finding the volume of the cube with not me than one err 3x 3x 3x 9x 2 3x 9 3 x 3 ( 9x 2 ) 3 Conceptual err 9x 2 = 9x (err) 9x 9x 9x = 729x 3 32

33 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 5 7, 6 8 Random numbers Crect response Additional guidance a a 98 Key not interpreted 9 8 b b Gives a crect explanation that refers to the dering of some all of the numbers He could find the row with the 28 th number in it, then put that row in der to get the right one If the row f the 50s is put in der, it is easier He could put the numbers in each row in der of size Minimally acceptable explanation Order the 5 row The 6 th line needs to go in der Put it in der Incomplete increct explanation He should rearrange the diagram He needs to put the middle row in der U1! Explanation refers to producing a cumulative frequency chart As this is not the simplest method available, do not accept without a complete explanation of method 33

34 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 5 7, 6 8 Geometric mean Crect response Additional guidance a a 90 b b Indicates Yes and gives a crect explanation 2 8 = 16, but you can t find the square root of a native number Multiplying native by positive gives a native, but native is impossible The numbers must be both positive both native f a positive product, as you can t find the square root of a minus number! Indicates No Accept provided their explanation refers to imaginary numbers, accept You can use an imaginary number 4i, do not accept 4 Minimally acceptable explanation You can t find the square root of a minus number You can t find the square root of 16 U1 Incomplete increct explanation You can t find the square root When you do 16 the calculat would say err 2 8 = 16, which is not a square number It doesn t wk with native numbers The numbers must be both positive both native 2 8 = 18, but then you can t do 18 34

35 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 5 7, Crect response Additional guidance Sequences a a 2m Matches all four nth term rules crectly, ie 4n 4, 7, 12, 19,! Rule matched to me than one sequence F 2m, do not accept as a crect match (n + 1) 2 4, 8, 12, 16, n , 9, 16, 25, n(n + 3) 4, 10, 18, 28, Matches at least two nth term rules crectly b b 2m 4, 11, 30 and 67, in the crect der Gives at least two of the four crect terms, even if their positions are increct Shows the values 1, 8, 27 and 64 Shows a complete crect method f all four terms provided the cubed has been interpreted, even if there is further increct wking

36 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 5 7, Crect response Additional guidance Rhombus 2m 145 Shows the value 35 Shows a complete crect method with not me than one computational err = 70, ( ) = = 25 (err) = Crect response Additional guidance Counters 2m 5 Shows implies that half the counters are green that half are red black = = 3 6 Green is = 1 2 Total = 30 Red + black = 15 U1 Shows implies a complete crect method with not me than one computational err

37 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 5 7, 6 8 Marking overlay available Crect response Additional guidance Fence plan 2m Completes the perpendicular bisect, fulfilling the four conditions below: 1. Ruled 2. Within the tolerance as shown on the overlay 3. Touching crossing both roads 4. Evidence of crect construction arcs that are centred on A and B, are of equal radii, and show at least one intersection! Use of construction arcs on the overlay Note that these are to give a visual guide as to whether the crect centres have been used, and do not indicate tolerance Spurious construction arcs Do not accept arcs drawn without compasses arcs that do not show a distinct intersection, arcs that just touch! Perpendicular bisect is not a solid line Condone provided the pupil s intention is clear Completes the perpendicular bisect with all of conditions 1 to 3 fulfilled Fulfils condition 4, even if the perpendicular bisect is increct omitted Crect response Additional guidance Powers 12 4! Answer embedded in wking Accept provided there is no ambiguity and any statements made are crect, f the first mark accept 5 12 [shown in wking] Otherwise, penalise only the first occurrence, f the first and second marks m = 5 12 n = 5 4 Mark as 0, 1! Incomplete processing Penalise only the first occurrence, f the first and second marks Mark as 0, 1 37

38 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 5 7, Crect response Additional guidance Dissection 2m Gives both crect pairs of dimensions A: 6cm by 8cm (either der) B: 2cm by 8cm (either der) Gives one crect pair of dimensions, even if assigned to the increct rectangle 6cm by 8cm (either der) seen 2cm by 8cm (either der) seen Shows implies that the ratio of the shter side of A to the shter side of B is also 3 : 1, even if there is incomplete processing other increct wking 6, 2 seen as shter sides 48 8, x = 8y Answer of A: 3cm by 4cm B: 1cm by 4cm The side of the square is 6cm (err), so A is 4.5cm wide and B is 1.5cm wide 48, 16 seen without further processing 38

39 2007 KS3 Mathematics test mark scheme: Paper 1 Tiers 5 7, Crect response Additional guidance Coins 2m Gives the crect set of eight coins, ie 1p, 1p, 2p, 2p, 2p, 2p, 5p, 10p in any der Shows the set of four coins 1p, 2p, 2p, 20p U1 Shows evidence of understanding that the total number of coins must be 4x and the number of 1p coins must be x, where x 1 1p, 1p, 2p, 2p, 2p, 5p, 5p, 10p It could be three 1p coins and twelve coins altogether F every four coins there is one 1p and three that are not 1p F, number of coins is not a multiple of 4, even if total value is 25p 1p, 1p, 2p, 2p, 2p, 2p, 5p, 5p, 5p 39

40 2007 KS3 Mathematics test mark scheme: Paper 1 Tier 6 8 only Increases by 3 19 Crect response Additional guidance 2m Gives all three crect values, ie Gives two crect values! Incomplete processing Withhold only f the first occurrence, f accept ! F, follow through F the second value, accept their first value 2, provided this does not give a value of 0 2 F the third value, accept their first value 3 their second value 3 2, provided this does not give a value of

41 2007 KS3 Mathematics test mark scheme: Paper 1 Tier 6 8 only 20 Crect response Additional guidance Perimeters a Draws the crect triangle in any ientation! Lines not ruled accurate Accept provided the pupil s intention is clear! Side lengths labelled Igne, even if increct b Draws a crect shape in any ientation, ie 41

42 2007 KS3 Mathematics test mark scheme: Paper 1 Tier 6 8 only Me powers 21 Crect response Additional guidance Crect response Additional guidance Threes a Indicates Odd and gives a crect explanation Odd odd = odd and since 3 is odd, it doesn t matter how many times you do the answer will still be odd 3 is odd, so 3 3 gives an odd answer 9, then 9 3 gives an odd answer 27 and so on Minimally acceptable explanation that states implies that 3 is odd Odd odd = odd and 3 is odd It s and odd odd = odd 3 is odd, so multiplying it by itself over and over again will always give an odd answer Any power of an odd number is odd, 3 2 = 9 Incomplete increct explanation Odd odd = odd You get 3 2 = 9, 3 3 = 27 etc and they always come out to be odd It s 3 multiplied by itself 100 times It can t be even Whenever 3 has a power the answer is always odd Because 3 is an odd number Multiplying by 3 always gives an odd answer U1 b Indicates only the value 3 200, ie 42

43 2007 KS3 Mathematics test mark scheme: Paper 1 Tier 6 8 only 23 Crect response Additional guidance a 7 Tan 35 b Gives the value 70 with a crect method, including evidence that the height of the triangle has been taken as = = = 70 tan Method used is accurate scale drawing! Follow through Accept follow through as 10 their (a) instead of 70 and their (a) instead of 7, with their (a) as 0.07 accept =

44 2007 KS3 Mathematics test mark scheme: Paper 1 Tier 6 8 only 24 Crect response Additional guidance Tests a Indicates False and gives a crect explanation The median was about 44.5 The median is at the 2500th value and when you read the graph down from that value you can see it is greater than 40 Only 1750 pupils got up to 38 marks and you need 2500 f the median About 1750 pupils sced 38 less which is the 35th percentile Up to 38 is only 1750 pupils and that s less than half! Range of values F the median on paper 1, accept 44 to 45 inclusive F the position of the median, accept F a value cresponding to a mark of 38, accept 1700 to 1800 inclusive, 34% to 36% inclusive Minimally acceptable explanation 44 to 45 inclusive seen Crect value f the median on paper 1 marked on x-axis The 2500th mark is bigger than and 2500 seen 1750 and 35% seen Incomplete explanation The 2500th value is not is not in the middle of the cumulative frequency 38 is too small to be the median Most pupils sced me than 38 b Indicates True and gives a crect explanation The LQ is about 33.5 The UQ is about = 23 Indicates either True False and gives evidence that the inter-quartile range is between 22 and 24 inclusive, excluding 23 The LQ is about 33 The UQ is about = 24! Range of values F the lower quartile on paper 1, accept 33 to 34 inclusive F the upper quartile on paper 1, accept 56 to 57 inclusive F the position of the lower and upper quartiles, accept and respectively Minimally acceptable explanation Crect values f the lower and upper quartiles on paper 1 marked on x-axis 33 to 34 inclusive and 56 to 57 inclusive seen From the 1250th to the 3750th marks is about 23 Incomplete explanation The lower quartile taken away from the upper quartile gives 23 [no indication of quartiles on graph] 44

45 2007 KS3 Mathematics test mark scheme: Paper 1 Tier 6 8 only 24 Crect response Additional guidance Tests (cont) c Indicates False and gives a crect explanation U1 The most common crect explanations: Use values from the graph The median on paper 1 is 44.5, the median on paper 2 is 51.5, so paper 1 is harder About 850 pupils got less than 30 marks on paper 1 but only about 250 did on paper 2 About 400 pupils got me than 65 marks on paper 1, but about 600 did on paper 2 Use interpret the relative positions of the lines The graph f paper 2 is always lower The dotted line is always on the right of the other line The marks on paper 2 were higher! Range of values F the median on paper 1, accept 44 to 45 inclusive F the median on paper 2, accept 51 to 52 inclusive F any other values on the x-axis, accept the crect values 0.5 F cresponding values on the y-axis, accept the crect values 50 Minimally acceptable explanation The median on paper 1 is lower than the median on paper 2 Me people got lower marks [paper 1 implied] Fewer people got lower marks on paper 2 Me people got better marks on paper 2 The line f paper 1 is higher Incomplete increct explanation Paper 2 was easier Everybody s sce is higher in paper 2 than in paper 1 45

46 2007 KS3 Mathematics test mark scheme: Paper 1 Tier 6 8 only 25 Crect response Additional guidance Circle angle 2m 50, with no evidence of an increct method Shows implies that angle ABC is 90 Shows a complete crect method with not me than one computational err = 40, Crect response Additional guidance Inequalities Gives two non-zero values x then y such that x > y and either x < 0 y < Gives two non-zero values x then y such that x < y and either x < 0 y <

47 2007 KS3 Mathematics test mark scheme: Paper 1 Tier 6 8 only Drawing triangles 27 Crect response Additional guidance Indicates No and gives a crect explanation The most common crect explanations: Show how the two triangles could be different One could draw: Minimally acceptable explanation The 5cm side could be in different places compared to the angles cm But the other one could draw: 60 5cm 20 There are 3 different triangles possible because the 5cm side could be opposite the 20, the 60 the other angle One could have those angles on either side of the 5cm line, but the other could have those angles on either side of a different line! Diagrams inaccurate Accept provided the response makes the position of the 5cm sides relative to the angles clear, accept Incomplete explanation They could have drawn three different triangles The angles are the same but the lengths may be different U1 Reason generally from known facts F them to be congruent, you need to know that the positions of the angles and sides crespond in the two triangles It needs to be AA cresponding side, but we don t know the der in the two triangles Minimally acceptable explanation You don t know if there are cresponding sides Incomplete explanation You don t know the arrangement of the side and angles, so you can t be sure 47

48 2007 KS3 Mathematics test mark scheme: Paper 1 Index Index to mark schemes Tier Question Page Euros 11 2 Number line times table 12 4 Feeding times 13 5 Wk out 13 6 Dollars 14 7 Divisibility Populations Number grids Babies Cards f fractions Pentagon perimeter Multiple and fact Same number Squares x = Grid Sweets Completing calculations Rectangles Percentages Positive and native Barrels 24 48

49 2007 KS3 Mathematics test mark scheme: Paper 1 Index Tier Question Page Speed Grey and black designs Counter probabilities Three straight lines Ninths Equation Circle wking Thinking fractions Cube Random numbers Geometric mean Sequences Rhombus Counters Fence plan Powers Dissection Coins Increases by Perimeters Me powers Threes Tan Tests Circle angle Inequalities Drawing triangles 47 49

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