Class 6 Logical Reasoning

Transcription

1 ID : in-6-logical-reasoning [1] Class 6 Logical Reasoning For more such worksheets visit Answer the questions (1) What is the 18 th term of the series (2) Find the missing term. (3) When a number is put into the machine below, a different number comes out. If 9 goes in, 4 comes out. If 11 goes in, 6 comes out. If 12 goes in, 7 comes out. 14 Number Machine? If 14 goes in, what number should come out? (4) Harsh mixed some single digit numbers in the box shown below. Write the fraction representing the total number of 9's among the given numbers (5) There are equal number of pens in each box. If there are 25 pens in 5 boxes, how many pens are there in all the 7 boxes?

2 ID : in-6-logical-reasoning [2] (6) Few cadets are standing in a row. Madhav is at the 20 th position from the front, and Ridhima is standing at the 12 th position from the back. If Madhav and Ridhima interchange their positions, Ridhima becomes 18 th from the back. How many cadets are there in the row? (7) If A B means A + B 2, what is the value of 2 (4 8)? (8) A survey was done in all schools of Lucknow, where each student was asked for their favorite colour. Result of survey is shown in the circle chart. Which is the least liked colour among students in Lucknow? (9) During a day, the hour hand and the minute hand of a clock form a right angle, at multiple times. For example, the two hands form a right angle at 9 am. How many times during a day (24 hours) will the two hands form a right angle? (10) If, = 3 = 12 = 9 = 21 Find the value of. (11) If sum of both diagonals are same, find the missing value

3 (12) Find the number of corners in the given shape. ID : in-6-logical-reasoning [3] (13) Lovleen and Bala are ranked 7 th and 8 th respectively from the top in a class of 47 students. What are their respective ranks from the bottom? (14) = Rs = Rs = Rs = Rs. 18 What is the cost of? Choose correct answer(s) from the given choices (15) The following bar chart shows the number of fruits in a shop. There are less papayas than pineapples. a. 70 b. 80 c. 50 d Edugain ( All Rights Reserved Many more such worksheets can be generated at

4 Answers ID : in-6-logical-reasoning [4] (1) 6 If you observe this series, you will notice the following: - First term is 1 - Next 2 terms (2 nd to 3 rd terms) are 2. - Next 3 terms (4 th to 6 th terms) are 3. - Next 4 terms (7 th to 10 th terms) are 4. - Next 5 terms (11 th to 15 th terms) are 5.. Similarly, we can find the subsequent terms as follows: - Next 6 terms (16 th to 21 st terms) will be 6. - Next 7 terms (22 nd to 28 th terms) will be and so on. Hence, 18 th term is 6. (2) 20 Let us observe this picture, and find the difference between consecutive numbers anti clockwise, 5-2 = = = 5? - 14 = ? = -- We can see that the difference between consecutive terms is increasing by 1. So if this pattern is to continue? - 14 = 6 and 27 -? = 7 Above relationships hold true only when the missing number is 20. Therefore, the missing number is 20.

5 (3) 9 ID : in-6-logical-reasoning [5] Let us write all pairs of input and output numbers, If we observe these numbers, we can see that the output number is 5 less than the input number. Same pattern should be followed when number 14 goes in, therefore output number, = 14-5 = 9 (4) 5 42 We can see that there are 42 numbers in the box. Now, lets count number of 9 in the box, Total number of 9 in the box = 5 The fraction representing the total number of 9's among the given numbers = 5 42

6 (5) 35 ID : in-6-logical-reasoning [6] According to the question, there are equal number of pens in each box. Number of pens in 5 boxes = 25 So, number of pens in one box = 25 5 = 5 Number of pens in one box = 5 So, number of pens in 7 boxes = 5 7 = 35 Therefore, the number of pens in 7 boxes are 35. (6) 37 Let us consider the position of Ridhima. She is standing at the 12 th position from the back. After interchanging positions with Madhav, she becomes 18 th from the back. The new position of Ridhima is also the 20 th position from the front (It is the same position where Madhav was standing earlier i.e. the 20 th position from the front). Ridhima is 18 th from the back, which means there are 17 cadets to her back. She is also 20 th from the front, which means there are 19 cadets to her front. Step 4 Therefore, the number of cadets in the row is 17 (back) + 19 (front) + 1 (Ridhima) = 37 cadets.

7 (7) 4 ID : in-6-logical-reasoning [7] Since, A B means A + B 2 2 (4 8) = 2 ( , the value of 2 (4 8), ) 2 (4 8) = 2 ( 12 2 ) 2 (4 8) = 2 6 Again use, A B = A + B 2 2 (4 8) = (4 8) = 8 2 Therefore, 2 (4 8) = 4 (8) Red If you look at the circle chart carefully, you will notice that the colour which has least survey in circle chart is Red. The colour which has least survey in circle chart, is the least liked colour among students in Lucknow, therefore the least liked colour among students in Lucknow is Red.

8 (9) 44 ID : in-6-logical-reasoning [8] Let us look at the clock at 9 am: We can see that the hour hand and the minute hand are making a right angle. In a clock, while the minute hand moves, the hour hand also moves, although a lot slowly. It is easy to see that in a 12 hour period, the minute hand make 12 revolutions while, the hour hand makes one. We can visualize the above statement this way: If we hold the clock in our hands and always keep on rotating it slowly, such that the hour hand always stay on the same position, the minute hand will make 12-1 = 11 revolutions. In other words, the minute hand makes 11 revolutions around the hour hand in a 12 hour period. For each revolution around the hour hand, the minute hand makes a right angle twice with it. The total number of times we see the two hands making a right angle is 11 2 = 22. Step 4 In 12 hours, the number of times the two hands make a right angle = 22 In 24 hours, the number of times the two hands make a right angle = 22 2 = 44

9 (10) 24 ID : in-6-logical-reasoning [9] Let us first try to find the value of each one of,, and. Given, = 3 Since, the value of 3 is 3. The value of will be = 3 3 = 1 Next we are told: = 12 We can use the above equation to find the value of. We know = 1 So, = 4 1 = 4 We can now say, + 4 = 12,or = 12-4 = 8 Since, the value of 2 = 8 The value of will be = 8 2 = 4 Step 4 Similarly calculating the values of and. We have, = 3 and = 3 Step 5 Now, it is easy to find the value of by substituting the value of each shape found above. = = = (Remember to do all multiplications before doing additions to make sure your answer is right!) = 24

10 ID : in-6-logical-reasoning [10] (11) 6 Lets find sum of top-right to bottom-left diagonal where all terms are known, = 22 Now lets find sum of all available terms in top-left to bottom-right diagonal, = 16 Since it is given that sum of both diagonals are same, missing terms must be equal to different of above two sum. Therefore missing term = = 6 (12) 10 A corner is the meeting point of two sides. If we count the number of corners in the figure it comes out to be 10. (13) 41 st and 40 th Let us look at a class of 3 students: Rank from top: Students: A B C Rank from bottom: With a class of 4 students: Rank from top: Students: A B C D Rank from bottom:

11 Do we see any pattern here? Yes For each student: Rank from top + Rank from bottom = 1 + Number of students in class Let us verify for class of 3 students: ID : in-6-logical-reasoning [11] Rank from top: Students: A B C Rank from bottom: Sum of ranks: Class of 4 students: Rank from top: Students: A B C D Rank from bottom: Sum of ranks: Lovleen and Bala are ranked 7 th and 8 th respectively from the top in a class of 47 students. For both of them, the sum of their ranks from top and bottom will be: = 48. For Lovleen: 7 + Her rank from the bottom = 48. This means, her rank from bottom = 48-7 = 41 st For Bala: 8 + Her rank from the bottom = 48. This means, her rank from bottom = 48-8 = 40 th

12 (14) 9 ID : in-6-logical-reasoning [12] Let us consider the last equation. It says that cost of 3 is Rs. 18, so the cost of 1 will be Rs. 18 divided by 3, or Rs. 6. The second equation is: + + = Rs. 34 And the first equation is: = Rs. 44 We observe here that the first equation can be easily replaced here to get: Rs = Rs. 44 Which means that the cost of will be Rs Rs. 34 = Rs. 10. Substituting the value of in equation third. We have, + Rs Rs. 10 = Rs. 39 or, = Rs Rs. 20 = Rs. 19 Step 4 Substituting the value of and in equation second. We have, Rs. 6 + Rs = Rs. 34 or, Rs = Rs. 34 or, = Rs Rs. 25 or, = Rs. 9 Step 5 Thus, the cost of one will be Rs. 9.

13 (15) d. 60 ID : in-6-logical-reasoning [13] Let us draw a table representing the fruits' name and quantity with the help of the given bar chart. Fruit's name Fruit's quantity Apple 60 Pear 50 Banana 20 Papaya 10 Pineapple 70 Plum 40 Peach 30 From the table, we notice that the number of papayas in the shop = 10 The number of pineapples in the shop = 70 Now, the difference between the number of papayas and pineapples in the shop = = 60 Hence, we can say that there are 60 less papayas than pineapples.