3rd Grade. Relate Multiplication to Addition. Slide 1 / 234 Slide 2 / 234. Slide 4 / 234. Slide 3 / 234. Slide 5 / 234. Slide 6 / 234.

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1 Slide 1 / 234 Slide 2 / 234 3rd Grade Multiplication Slide 3 / 234 Table of Contents Relate addition to multiplication Arrays Multiply by 1 and 0 Multiply by 2 Multiply by 5 Multiply by 10 Multiplication Table Activity Multiply by 3 Multiply by 4 Multiply by 6 Multiply by 7 Multiply by 8 Multiply by 9 Square and Rectangles Unit squares and tiling - Area of Squares Area of rectangles Area Word Problems Slide 5 / 234 click on the topic to go to that section Slide 4 / 234 Relate Multiplication to Addition Slide 6 / 234 click to return to table of contents Relate Multiplication to Addition There are 5 students. Each student is holding up both hands in the air. How many hands are up in the air? Relate Multiplication to Addition The Greene brothers went for a bike ride. If all four went riding, how many bicycle wheels would you see? What are all of the ways you could figure out this answer? What are all of the ways you could figure out this answer?

2 Slide 7 / 234 Relate Multiplication to Addition Did you use addition? What would the number sentence look like? = 8 Click This is called repeated addition. Why do you think it is called this? Slide 8 / 234 Relate Multiplication to Addition Did you consider using multiplication? How many bicycles were there? How many wheels did each bicycle have? What would the number sentence look like? Click 4 X 2 = 8 Once you are able to memorize your multiplication facts, you will realize that it is the quickest way to solve problems like the Greene brothers' problem. Slide 9 / 234 Relate Multiplication to Addition Which number sentences match the picture of three flowers with 7 petals each? Slide 10 / 234 Relate Multiplication to Addition There are five jars. In each jar, there are 3 insects. Show all 5 jars with 3 insects in each jar in the space below. How many insects are there all together? Repeated Addition Multiplication 3 x 5= = = = What is the repeated addition sentence? 6 x 3= 3 x 7 = = What is the multiplication number sentence? Slide 11 / 234 Relate Multiplication to Addition Slide 12 / 234 Relate Multiplication to Addition How would you write 4 x 6 = in a repeated addition problem? How would you write 2 x 8 = in a repeated addition problem? What kind of picture could show these problems? What kind of picture could show these problems?

3 Slide 13 / 234 Slide 14 / 234 Multiplication Game Click to play Carl's Cookie Capers. 1 ) 2 x 5 = 5 + 5? True False Slide 15 / What would the repeated addition number sentence look like for the multiplication problem, 3 x 8 =? A = B = C 8 x 3 = D = Slide 16 / What would the multiplication number sentence look like for the repeated addition problem, =? A = B 3 x 5= C 5 x 5 = D 3 x 3 = Slide 17 / What repeated addition number sentence would help you figure out the number of petals in the picture below? A 2 x 7 = B = C = D = Slide 18 / What multiplication number sentence would help you figure out the number of petals in the picture below? A 2 x 7 = B = C = D =

4 Slide 19 / 234 Slide 20 / 234 What are Arrays? Arrays are rectangles made of organized rows and columns of objects to represent a certain number. An example, of the arrays for the number 6 are shown below. Arrays click to return to table of contents Slide 21 / 234 Using Arrays Now you try! Drag and place 8 soccer balls in an array on the field. How many different ways can you arrange the soccer balls so they are arranged into organized rows and columns? Slide 22 / 234 Using Arrays When writing a multiplication number sentence for an array, write the number of rows first. The second number should be the number in each row, or the number of columns. columns rows columns rows 4 x 2 2 x 4 Click to reveal the multiplication number sentence for each array. Slide 23 / 234 Using Arrays Each array below is an example of 6. What would the multiplication number sentence for each array be? Slide 24 / 234 Using Arrays Drag the stars into the rectangle to make an array showing 2 x 5. How many stars will it take to complete the array?

5 Slide 25 / 234 Using Arrays Circle the peanuts to show other ways to make arrays showing 10. Slide 26 / Are the cats arranged in an array? Yes No Slide 27 / This is an array for what number? Slide 28 / Which array is a model for 3 x 2? A the mice B the frogs C the flowers D none of the above Slide 29 / The multiplication number sentence for this array of shoes is 2 x 3. True False 10 What array is circled? A 2 x 6 B C 12 x 1 D 3 x 4 Slide 30 / 234

6 Slide 31 / 234 Slide 32 / 234 Multiplying by 0 When multiplying a number by 0, try to remember relating it to addition. Multiplying by 1 and 0 What would that equal? For example, 8 x 0 can be thought of as Could you make an array using 8 x 0? click to return to table of contents Slide 33 / 234 Multiplying by 0 Can you explain what happens every time a number is multiplied by 0? Slide 34 / 234 Multiplying by 0 When multiplying a number by zero, we call it Any number x 0 = 0 This is called the Zero Property of Multiplication. Slide 35 / 234 Multiplying by 1 When multiplying a number by 1, try to remember relating it to addition. For example, 8 x 1 can be thought of as Slide 36 / 234 Multiplying by 1 Can you explain what happens every time a number is multiplied by 1? What would that equal? What would an array of 8 x 1 look like? Use the circles to show the array. This is called the Identity Property of Multiplication.

7 Slide 37 / 234 Multiplying by 1 Slide 38 / 234 When multiplying a number by one, we call it Any number x 1 = itself Slide 39 / 234 Multiplying by 1 and 0 Game Click the tire to play a game. Slide 40 / The answer to 10 x 0 is 10. True False Slide 41 / Sandra wants to buy prizes from the machines in front of the store. She has to put in one coin in each machine. If there are 5 machines, how many coins will she need to buy a prize from each machine? Slide 42 / What is the answer to any problem that involves multiplying by 0? A 1 B 5 C 0 D 4

8 Slide 43 / 234 Slide 44 / ) 6 x 1 is an example of the Identity Property? Yes No 15 Greg gives each of his customers 2 coupons when they visit his store. If he hasn't had any customers today, how many coupons has he given out? A 2 B 1 C 0 Slide 45 / 234 Slide 46 / 234 Multiplying by 2 2 x 5 = 10 Factor Factor Product Multiply by 2 Factors are the numbers we multiply together to get to an answer which we call the product. When you are asked to multiply a number by the factor 2, what are some ways you could go about finding the answer? click to return to table of contents Slide 47 / 234 Slide 48 / 234 Multiplying by 2 Think of some words that mean 2. Click the numbers to reveal some.

9 Slide 49 / 234 Multiplying by 2 Multiplying by 2 can be thought of as doubling your factor. So, imagine that the problem 3 x 2 is 3 doubled, or 2 groups of 3. Slide 50 / 234 Double each set of animals below and write the multiplication number sentence to match. Slide 51 / 234 Multiplying by 2 Game Click the pencil to play a game. 16 ) 2 x 0 = 2 True False Slide 52 / 234 Slide 53 / 234 Slide 54 / If you were to double 4, what would be your answer? A 2 B 4 C 6 D 8 18 When you multiply a number by 2, the answer is always 2? Yes No

10 Slide 55 / Which number sentence matches the following word problem? Mr. Blake asked his students to take off their shoes for an activity and place them against the wall. If he has 9 students, how many shoes were along the wall? A = 10 B 9 x 2 = 9 C 9 x 9 = 81 D 9 x 2 = 18 Slide 56 / Which picture below shows an array where 2 was a factor? A peanuts B flowers C pigs D none of the pictures Slide 57 / 234 Slide 58 / 234 Multiplying by 5 Fill in the chart below. Factor Multiply by 5 x 5 What pattern do you see in the products of each factor? Could this be a rule? What do you notice about the digits in the ones place? click to return to table of contents Slide 59 / 234 Let's Practice! Using what your remember from the table you created in the last slide, practice multiplying 5 and the number you roll on the 6-sided dice. Click the dice to roll again. Slide 60 / 234 Multiplying by 5 What items do you think of when 5 is mentioned? Click each box for some ideas. 5 x = Can you use one of these items in a multiplication number story?

11 Slide 61 / 234 Multiplying by 5 For example, here's a number story using a factor of five. Natalie is saving up for a new painting set for her artwork. The new paint set costs $32. She can save $5 a week. If she saves her money for 7 weeks, will Natalie have enough money to purchase the new paint set? Slide 62 / 234 Practice Multiplying by 5 Now you try! Alone or with a partner, write and solve a multiplication word problem using number 5. What number sentence would you use to check your work? Slide 63 / 234 Slide 64 / 234 Multiplying by 5 Game Click the beach ball to play a multiplication of 5 game. 21 ) 9 x 5 = 40 True False Slide 65 / What number besides 5, could be in the ones place of the multiples of 5? Slide 66 / This wagon has 4 wheels. How many wheels would there be if there were 5 wagons? A 20 B 45 C 1 D 9

12 Slide 67 / 234 Slide 68 / It takes Jim 5 minutes to run one lap around the track. How many minutes does it take for him to run 8 laps? A 58 B 3 C 40 D Does knowing the multiples of 5 help you tell time? Yes No Slide 69 / 234 Slide 70 / If the big hand is on the 5, how many minutes past the hour is it? 27 If the big hand is on the 2, how many minutes past the hour is it? Slide 71 / Carol plays a ball game. She gets 7 points each time her ball hits a target. If she hits the target at least 5 times in a row, she gets an extra 25 points. What is the total number of points Carol gets if she hits the target 5 times in a row? Slide 72 / 234 Multiplying by 5 Reminder: Nickels are worth 5 cents. From PARCC EOY sample test #12

13 Slide 73 / 234 Multiplying by 5 Four friends each have a nickel, what is the total amount of money they have? 4 groups of 5 4 x 5 = 20 cents click click Slide 74 / You find six nickels under the couch. How many cents did you find? A 6 cents B 5 cents C 65 cents D 30 cents Slide 75 / 234 Slide 76 / A piece of candy is five cents. If you buy 8 pieces, how much will it cost? 31 Your aunt gives you five cents for each flower you help her plant. If you plant 3, how many cents will she give you? Slide 77 / 234 Slide 78 / While cleaning out your dad's car you find 9 nickels. How many cents is this? 33 In your piggy bank you have 7 nickels. How many cents is this?

14 Slide 79 / 234 Slide 80 / 234 Multiplying by 10 Fill in the chart below. Factor x 10 Multiply by 10 What pattern do you see in the products of each factor? Could this be a rule? What do you notice about the digits in the ones place? click to return to table of contents Slide 81 / 234 Multiplying by 10 Let's practice! Using what your remember from the table you created in the last slide, practice multiplying 10 and the number you roll on the 6- sided dice. Click the dice to roll again. Slide 82 / 234 Multiplying by 10 What items do you think of when 10 is mentioned? Click each box for some ideas. 10 x = Can you use one of these items in a multiplication number story? Slide 83 / 234 Multiplying by 10 For example, here is a multiplication number story using a factor of 10. Melissa is in a beginner's typing class. At the end of her first day she could type 10 words in one minute. How many words could she type if the teacher gave her 7 minutes to finish? Slide 84 / 234 Practice Multiplying by 10 Now you try! Alone or with a partner, write and solve a multiplication word problem using the number 10. What is the number sentence you would use to check your work?

15 Slide 85 / 234 Practice Multiplying by 10 When multiplying by 10, the rule is you are basically "adding a place value" to that number. So in the case of 10 x 5 = 50, we are "adding a place value" to 5 making it 50. This works for all numbers! Let's practice. Pop the balloons to check your answers. Slide 86 / 234 Multiplying by 10 Game Click to play a multiplication of 10 game Slide 87 / 234 Slide 88 / Multiples of 10 have in the ones place? A 10 B 1 C 0 D Both B and C 35 The product below is 10? Yes No Slide 89 / 234 Slide 90 / This bouquet has 3 flowers. How many flowers would there be if there were 10 bouquets? A 13 B You charge $10 for raking leaves. If you rake 7 yards, how much money will you earn? C 7 D 30

16 Slide 91 / While cleaning out your mom's car you find nine dimes. How many cents is this? A 9 B 19 C 90 D 900 Slide 92 / While shopping you buy five new shirts. Each one is $10. How much did you spend? Slide 93 / You can use the rule for 10 for numbers larger than 10. (for example, 13 x 10) 41 What is 21 x 10? Slide 94 / 234 True False Slide 95 / 234 Slide 96 / Which two ways show how to find the value of 7 x 40? Select two correct answers. 43 ) 3 x 80 = A 7 x 4 B 4 x 10 C 7 x 4 x 10 D 7 groups of 4 ones E 7 groups of 4 tens From PARCC EOY sample test #4 From PARCC EOY sample test #36

17 Slide 97 / 234 Slide 98 / 234 Multiplication Table Multiplication Table Activity click to return to table of contents Slide 99 / 234 Slide 100 / 234 Multiplying by 3 When given the multiplication problem of 6 x 3, you can picture 6 groups of 3. It can be helpful to use the circles as your groups. Make 6 groups with 3 pigs in each. Multiply by 3 click to return to table of contents Slide 101 / 234 Multiplying by 3 Counting by threes and creating arrays may also help you with your 3 times tables. Slide 102 / 234 Multiplying by 3 Fill out the multiplication chart below. 3, 6, x 3 Factors x Is there a pattern? What else do you notice about the products?

18 Slide 103 / 234 Multiplying by 3 Slide 104 / 234 Multiplication by 3 Game Click on the dinosaur to play a multiplication game. Slide 105 / 234 Slide 106 / The products of multiplication problems with 3 in them are all odd. True False 45 In Fairytale Town, there are 9 cottages that have 3 bears in each. How many bears are there in all? A 12 B 27 C 6 D 3 Slide 107 / What number was 3 multiplied by to make the array below? A 3 B 12 C 4 D 15 Slide 108 / Can a 3 times table have even numbers as products? Factors Yes No x3

19 Slide 109 / 234 Slide 110 / What is 3 x 8? Slide 111 / 234 Slide 112 / 234 Multiplying by 4 When given the multiplication of 3 x 4, you can picture 3 groups of four. It can be helpful to use the circles as your groups. Make 3 groups with 4 quarters in each. Multiply by 4 click to return to table of contents Slide 113 / 234 Multiplying by 4 Counting by fours and creating arrays may also help you with your 4 times tables. Slide 114 / 234 Multiplying by 4 Fill out the multiplication chart below. 4, 8, But have you heard of double doubling? You've been taught that multiplying by two can be done by doubling. If you double that one more time, you've multiplied by four. Factors x For example, 4 x 5 can be thought of as doubling 5. That will equal 10. Then double that, and you will have 20. So, 4 x 5 = 20. Is there a pattern? What else do you notice?

20 Slide 115 / 234 Multiplying by 4 Slide 116 / 234 Multiplying by 4 Another way to quickly recall multiplication facts is to think of your 2 times table and double that. Notice how the 4 times tables are double the 2 times tables. Slide 117 / 234 Practice Multiplying by 4 Let's multiply by 4. Roll the 6-sided dice to see by which factor you are multiplying the 4. Can you double the double? Once you find a product, you may pop that balloon. Play until all balloons have been popped. Slide 118 / 234 Multiplication by 4 Game Click on the snow to play a multiplication game. x = Slide 119 / 234 Slide 120 / The products of multiplication problems with 4 in them are all odd. 51 What is 4 x 8? True False

21 Slide 121 / 234 Slide 122 / The waitress gave us 4 packs of crayons when we sat down to eat. There were 4 crayons in each pack. How many crayons are there? A 8 B 0 C 16 D The number 36 has 4 as a factor. What is the other factor? A 9 B 32 C 40 D 0 Slide 123 / 234 Slide 124 / Does the picture show a multiple of 4? Yes No Multiply by 6 click to return to table of contents Slide 125 / 234 Multiplying by 6 When given the multiplication of 6 x 4, you can picture 6 groups of four. It can be helpful to use the circles as your groups. Make 6 groups with 4 x's in each. Slide 126 / 234 Counting by six and creating arrays may also help you with your 6 times tables. 6, 12, Multiplying by 6 6 x 3

22 Factors x6 Slide 127 / 234 Multiplying by 6 Fill out the multiplication chart below Is there a pattern? What else do you notice? Let's play a game of multiplication by 6 tic-tac-toe. o 6 x x Slide 128 / 234 Multiplication by 6 Game Slide 129 / 234 Multiplication by 6 Game Click on the fish to play a multiplication game. Slide 130 / The products of multiplication problems with 6 in them are all odd. True False Slide 131 / 234 Slide 132 / I rolled 4 dice. Each die landed on 6. What was the product of all of the dice? A 10 B 2 C 16 D What is not a multiple of 6? A 6 B 16 C 24 D 42

23 Slide 133 / 234 Slide 134 / Does the picture below show a multiple of 6? 59 What is 6 x 8? Yes No Slide 135 / 234 Slide 136 / 234 Multiplying by 7 If the seven swans a swimming decide to become seven swans a laying. How many eggs will there be after each lays six eggs? Multiply by 7 click to return to table of contents Use the nests and the eggs to show a picture to match the story problem. Slide 137 / 234 Multiplying by 7 Creating arrays may also help you with your 7 times tables. Use the pen to trace around the squares to make arrays with 7 as a factor. Slide 138 / 234 Multiplying by 7 Fill out the multiplication chart below. Factors x7 Is there a pattern? What else do you notice?

24 Slide 139 / 234 Multiplying by 7 Slide 140 / 234 Multiplication by 7 Game Click on the rocking horse to play a multiplication game. The baker has several birthdays coming up. If each cake receives 7 candles, how many candles will he need to order for the 9 cakes he has baked? The cake is infinitely cloned. What is your multiplication number sentence? Slide 141 / The products of multiplication problems with 7 in them are all odd. True False Slide 142 / The seven dwarves were getting ready to go to work. Each carried two pick axes. How many axes were there? A 9 B 5 C 72 D 14 Slide 143 / When in a word problem, what word could mean 7? A meter B Half dozen C week D octagon Slide 144 / If I had 5 of the following cards, would I have 35 hearts? Yes No

25 Slide 145 / 234 Slide 146 / What is 7 x 8? Multiply by 8 click to return to table of contents Slide 147 / 234 Multiplying by 8 If 7 itsy bitsy spiders crawl up to the top of a wall, how many spider legs will there be in all? Slide 148 / 234 Multiplying by 8 Creating arrays may also help you with your 8 times tables. Use the pen to trace around the squares to make arrays with 8 as a factor. Factors x8 Slide 149 / 234 Multiplying by 8 Fill out the multiplication chart below Slide 150 / 234 Multiplying by 8 Mario is the head chef at Tony's Pizza House. He makes sure each pizza is cut into 8 slices. How many slices of pizza will there be if Mario serves 5 pizzas during his lunch rush? The pizzas are infinitely cloned. Is there a pattern? What else do you notice? What is the multiplication number sentence you could use?

26 Slide 151 / 234 Multiplication by 8 Game Click on the bear to play a multiplication game. Slide 152 / The products of multiplication problems with 8 in them are all even. True False Slide 153 / Most jobs ask you to work 8 hours a day for 5 days each week. How many hours is that in all? A 13 B 3 C 40 D 85 Slide 154 / When in a word problem, what word could mean 8? A ate B Half dozen C week D octagon Slide 155 / This is an array that shows 8 x What is 9 x 8? Slide 156 / 234 Yes No

27 Slide 157 / 234 Slide 158 / Which two statements can be represented by the expression 4x8? A A teacher puts 8 chairs at each of 4 tables. B Tom buys 4 red markers and 8 black markers. C Marie shares her 8 marbles equally among 4 friends. D There are 4 rows of flowers. There are 8 flowers in each row. E There are 8 ducks in the pond. Then, 4 more ducks join them. Multiply by 9 From PARCC EOY sample test #2 click to return to table of contents Slide 159 / 234 Multiplying by 9 A cat is said to have 9 lives. If there were six cats, how many "lives" would they have altogether? Slide 160 / 234 Multiplying by 9 Creating arrays may also help you with your 9 times tables. Use the pen t trace around the squares to make arrays with 9 as a factor. Slide 161 / 234 Multiplying by 9 There is also a strategy for your 9 times tables using your hands. Slide 162 / 234 Multiplying by 9 Place your hands in front of you like so. If you put down your left pinky, how many fingers do you have up? If you put down your next finger, how many fingers do you have to the left of that finger? How many fingers do you have to the right? If you put down your next finger, how many fingers do you have to the left of that finger? How many fingers do you have to the right?

28 Slide 163 / 234 Multiplying by 9 Fill out the multiplication chart below. Factor x 9 Is there a pattern? What else do you notice? Slide 165 / 234 Slide 164 / 234 Multiplying by 9 Game Click on the window to play a multiplication game. Slide 166 / The products of multiplication problems with 9 in them are all even. True False 72 Nine teachers each have 4 computers in their classrooms. How many computers is that in all? A 13 B 5 C 36 D 94 Slide 167 / What number is not a multiple of 9? A 9 B 19 C 27 D 90 Slide 168 / If there are 9 starfish, there would be 45 legs? Yes No

29 Slide 169 / 234 Slide 170 / What is 9 x 8? 76 Cade has 4 boxes. He puts 9 model cars in each box. What is the total number of model cars Cade put in these boxes? From PARCC EOY sample test #25 Slide 171 / 234 Slide 172 / 234 Squares A square is a shape where all four sides are the same length. The four corners are all right angles. Squares & Rectangles click to return to table of contents Slide 173 / 234 Slide 174 / 234 Rectangles A rectangle is a four sided shape. All four corners are right angles.

30 Slide 175 / 234 Squares & Rectangles Slide 176 / 234 A square is a shape where all four sides are the same length. The four corners are all right angles. A rectangle is a four sided shape. All four corners are right angles. It is important to remember that because of the definition of a RECTANGLE, all squares are in fact rectangles. They meet the definition in that they have four sides and all four corners are right angles. A rectangle is only a SQUARE when all four sides are the same length and all four corners are right angles. Slide 177 / Choose all of the below that are squares. Slide 178 / Choose all of the below that are rectangles. A B C D E F A B C D E F 79 Is a square a rectangle? Yes No Slide 179 / Is a rectangle a square? Yes No Slide 180 / 234

31 Slide 181 / 234 Slide 182 / 234 What is Area? Area is the space inside of an object. Unit Squares and Tiling - Area of Squares For example, in a backyard the grass inside the fence makes up the area of the yard. fence = perimeter grass = area click to return to table of contents A unit square, is a square that has side lengths of one. Slide 183 / 234 What is Area? Area is the number of square units it takes to cover the surface of a unit. 1 unit 1 unit On grid paper, make a square that has sides of 3 units. Slide 184 / 234 Area How many unit squares would you need to cover the area of the square? unit square Slide 185 / 234 Area Slide 186 / The area is the part around the outside of a shape. Now make a square that has sides of 4 units. True False How many unit squares would you need to cover the area of the square? unit square

32 Slide 187 / 234 Slide 188 / How many unit squares will it take to cover this square? 83 How many unit squares will it take to cover this square? Slide 189 / If a square has side lengths of 7, how many unit squares do you think it will take to cover it? (Do not draw this example.) Slide 190 / 234 Finding the Area of a Square Area can be found by counting the unit squares on a grid. It is also found by multiplying the length and the width of a square. Because of the definition of a square, we know that each side has the same length. Sometimes, length and width are called base and height. These two measurements are also called the dimensions. Identify the parts of the rectangle below. Drag words from the bubble to show where they belong. AREA or length width base height or Square Side Lengths Slide 191 / 234 Area of a Square Number of Unit Squares to Cover Teacher Notes Slide 192 / What is the area of a square with side lengths of 9 units? square units

33 Slide 193 / 234 Slide 194 / What is the area of a square with side lengths of 10 units? 87 What is the area of a square with side lengths of 1 inch? units 2 square inches Slide 195 / 234 Slide 196 / 234 Area of Rectangles On grid paper, make a rectangle that has sides of 3 units by 2 units. Area of Rectangles How many unit squares would you need to cover the rectangle? unit square click to return to table of contents On grid paper, make a rectangle that has sides of 3 units by 6 units. Slide 197 / 234 Area of Rectangles On grid paper, make a rectangle that has sides of 4 units by 5 units. Slide 198 / 234 Area of Rectangles How many unit squares would you need to cover the rectangle? unit square How many unit squares would you need to cover the rectangle? unit square

34 On grid paper, make a rectangle that has sides of 5 units by 3 units. Slide 199 / 234 Area of Rectangles Slide 200 / 234 Finding the Area of a Rectangle Area is found by counting the unit squares taken up by a grid. It can also be found by multiplying the length and the width of a rectangle. Sometimes, length and width are called base and height. These two measurements are also called the dimensions. How many unit squares would you need to cover the rectangle? unit square Identify the parts of the rectangle below. Drag words from the bubble to show where they belong. AREA or length width base height or Slide 201 / 234 Slide 202 / 234 Sometimes, you are given the length and width of a rectangle. Multiply them together to find the area. 8 Area of Rectangles 3 length x width = area 8 x 3 = 24 the area is 24 Rectangle Length Area of Rectangles Rectangle Width Number of Unit Squares to Cover Teacher Notes Slide 203 / 234 In other cases, you may only know the measure of one side and the total area. Your job is to find the length of the remaining side. Think: length x = area Use what you already know about multiplication and fact families to help you find the missing width. For example, Area of Rectangles?? 5 x? = 45 Let's help solve a problem! Slide 204 / 234 Tyler is a home painter. He knows he will need enough paint to cover a wall area of 80 square feet. The wall is 10 feet wide. What is the length of a wall? What do we already know? We know the width and the area. Let's use our fact families to figure out the length of the wall. feet x 10 feet = 80 square feet 8 feet x 10 feet = 80 square feet Practice 5 The length must be 9 because 5 x 9 = 45

35 Slide 205 / 234 Area of Rectangles Game Click the button to play a game. Slide 206 / How many unit squares will it take to cover this rectangle? square units Slide 207 / How many unit squares will it take to cover this rectangle? Slide 208 / Look at the shaded rectangles below. Which area would you drag to label below Rectangle Number 3? square units feet 4 feet 6 feet 9 feet 7 feet 3 feet A 20 square feet B 24 square feet C 27 square feet D 28 square feet From PARCC EOY sample test #19 Slide 209 / If a rectangle has side length of 7 and a side width of 3, how many unit squares do you think it will take to cover it? (Do not draw this example.) Slide 210 / If a rectangle has side length of 5 and a side width of 8, how many unit squares do you think it will take to cover it? (Do not draw this example.) units 2 units 2

36 Slide 211 / 234 Slide 212 / What is the area of a rectangle with a side length of 10 feet and a side width of 3 feet? 94 What is the area of a rectangle with a side length of 1 inch and a side width of 3 inch? square feet in 2 Slide 213 / 234 Slide 214 / Which rectangle has an area of 24 square units? A C Area Word Problems B D click to return to table of contents From PARCC PBA sample test #14 Slide 215 / 234 Area Word Problems As with any word problems, read each carefully to make sure you understand the problem. You may draw pictures and use multiplication to solve each problem. Slide 216 / A rectangular field measures 10 ft by 4ft. What is the area of this field? feet 2 The units are important. Do not forget to include them in your answer.

37 Slide 217 / 234 Slide 218 / Cooper wants new carpeting for his bedroom. His room is 5 yd by 8 yd. How much carpeting does he need to buy to cover his bedroom floor? square yards 98 Mrs. Clark decided to change the tile in her classroom. Her classroom has a length of 7 m and the width of 10 m. If each tile is 1 square meter, how many tiles would she need to cover the floor? tiles Slide 219 / 234 Slide 220 / There is a square garden with the side length of 7 m. What is the area of the garden? 100 The area of a square photo is 25 square inches. What is the length of one of the sides of the photo? m 2 inches Slide 221 / 234 Slide 222 / Mr. George is building square platforms for students to reach their SMARTboards. Can he build one with the area of 56 square inches? 102 Janie is covering a bulletin board for the school talent show. The board is 9 ft by 5 ft. How many square feet of paper will she need to cover the board? feet 2 Yes No

38 Slide 223 / Each side of our kitchen TV is 9 inches long. What is the area of the TV screen? inches 2 Slide 224 / I counted the squares that were inside the rectangle I drew. There were 48 squares. What are the side lengths of my rectangle (dimensions)? A 7 x 7 B C 6 x 8 D 48 x 2 Slide 225 / A room has an area of 24 square feet. Its length is 3 feet long. What is the width? feet Slide 226 / Jenny is making a box garden in her backyard. The length of her box garden is 8 yards. The area inside where she will fill dirt is 72 square yards. What is the width of her box garden in yards? Slide 227 / Ken draws a rectangle with an area of 35-square inches. The width of the rectangle is 5 inches. What is the length of Ken's rectangle? Slide 228 / Mr. James is covering his bulletin boards with paper to start the new school year. His bulletin board is 7 feet wide, and he has already cut 56 square feet of red paper. Determine the length of his bulletin board. A 9 feet B 8 feet C 7 feet Welcome to Mr. J's Class D 6 feet From PARCC EOY sample test #27

39 Slide 229 / Cathy purchased a new tablecloth for her birthday party. The area of the tablecloth is 24 square feet. What are possible dimensions of the tablecloth? Choose all that apply. A 12 ft x 12 ft B 8 ft x 3 ft C 5 ft x 8 ft D 6 ft x 4 ft Slide 230 / Gina's bedroom floor is in the shape of a rectangle. It is 10 feet long and 9 feet wide. What is the area of Gina's bedroom floor? A 19 square feet B 38 square feet C 90 square feet D 109 square feet From PARCC PBA sample test #1 111 Part A Slide 231 / 234 Tori and Leo set up their clubhouse with four tables. These rectangles represent the tabletops. A B C D From PARCC PBA sample test #8 Slide 233 / 234 Enter the two tabletops with the same area, in square feet, and explain how you know that the areas are equal. 113 Adam needs to put 19 pictures from Classroom A and 23 pictures from Classroom B on a bulletin board. He wants to display the pictures in an array. Part A Select a box for each pictures to create an array to represent the pictures on the bulletin board. 112 Part B Slide 232 / 234 The grid shows Table C and Table D placed end to end to make a new, larger tabletop. Tori uses the expression 3 x (2 + 4) to find the total area of the new, larger tabletop. Leo uses the expression (3 x 2) + (3 x 4) to find the total area of the new, larger tabletop. Enter the total area, in square feet, of the new, larger tabletop. Use a grid to explain why both Tori's expression and Leo's expression are correct. From PARCC PBA sample test #8 Slide 234 / Part B (continued from previous slide) Find the area of the array. Explain your answer using an equation or equations. From PARCC PBA sample test #9 From PARCC PBA sample test #9