Understanding Properties and Calculating Fabric Costs

The video tutorial explains how to use the commutative and associative properties to simplify the multiplication of rational numbers. It uses a practical example of calculating the total cost of fabric needed for costumes. The teacher demonstrates how to rearrange terms in a multiplication expression to make calculations easier, ultimately finding the total cost of the fabric.

What is the commutative property used for in multiplication?

• Changing the order of numbers

• Grouping numbers differently

• Distributing numbers

• Adding numbers

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CCSS.2.OA.A.1

How many costumes does Miss Moore need to make?

• 10

• 13

• 20

• 15

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CCSS.6.RP.A.1

CCSS.6.RP.A.2

What is the cost per yard of fabric?

• $10

• $6

• $5

• $8

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CCSS.5.MD.B.2

How much fabric is needed for each costume?

• 3/4 yard

• 1/2 yard

• 1 1/4 yards

• 1 yard

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CCSS.7.EE.B.3

What expression represents the total amount of fabric needed?

• 13 / 3/4

• 13 + 3/4

• 13 x 3/4

• 13 - 3/4

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CCSS.3.OA.B.5

Which property allows you to rearrange the terms in a multiplication expression?

• Commutative property

• Identity property

• Associative property

• Distributive property

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CCSS.7.NS.A.1D

Why is it beneficial to rearrange the expression using the associative property?

• To make the expression longer

• To change the result

• To simplify calculations

• To make the expression more complex

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CCSS.4.NF.B.4B

CCSS.4.NF.B.4C

What is the result of multiplying 8 by 3/4?

• 6

• 24

• 8

• 12

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CCSS.3.OA.D.8

What is the final total cost of the fabric?

• $78

• $64

• $84

• $52

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CCSS.5.NBT.B.7

What is the purpose of changing 8 to 8 over 1 in the calculation?

• To add it to another number

• To divide it by another number

• To make it a fraction for easier multiplication

• To subtract it from another number

Tags

CCSS.5.NBT.B.7