Understanding Proportions through Cross Multiplication

Front

What is the purpose of cross multiplication in solving proportions?

Back

To find the value of the unknown variable.

Tags

CCSS.7.RP.A.2C

Front

What mathematical operation is primarily used to solve proportions?

Back

Cross multiplication.

Tags

CCSS.7.EE.B.3

Front

What does the equation 9M = 72 tell us about the value of M?

Back

M is exactly 8.

Tags

CCSS.3.OA.B.6

Front

How do you solve for M in the equation 9M = 72?

Back

Divide both sides by 9.

Tags

CCSS.6.EE.B.7

Front

How is the value of X found in the equation 20X = 120?

Back

By dividing both sides by 20.

Tags

CCSS.HSA.REI.A.1

Front

What is a proportion?

Back

A statement that two ratios are equal.

Tags

CCSS.7.RP.A.2A

Front

If a/b = c/d, what does cross multiplication involve?

Back

Multiplying a by d and b by c.

Tags

CCSS.5.NF.B.5B

Front

What is the first step in solving a proportion?

Back

Set the two ratios equal to each other.

Tags

CCSS.7.RP.A.3

Front

What is the result of cross multiplying 3/4 = x/8?

Back

3 * 8 = 4 * x.

Tags

CCSS.3.NF.A.3B

CCSS.4.NF.A.1

Front

How can you check if your solution for a proportion is correct?

Back

Substitute the value back into the original proportion.

Tags

CCSS.7.EE.B.3