Solving Proportions

Front

What is a proportion?

Back

A proportion is an equation that states that two ratios are equal.

Tags

CCSS.7.RP.A.2A

Front

How do you solve for x in a proportion?

Back

Cross-multiply the ratios and then solve for x.

Tags

CCSS.7.RP.A.2C

Front

What does it mean if two ratios do not form a proportion?

Back

It means that the two ratios are not equal to each other.

Tags

CCSS.6.RP.A.3A

Front

If the ratio of boys to girls is 3 to 2, how can you find the number of girls if you know the number of boys?

Back

Use the ratio to set up a proportion: 3/2 = 12/x, then solve for x.

Tags

CCSS.7.RP.A.3

Front

What is the first step in solving a proportion?

Back

Identify the two ratios that are being compared.

Tags

CCSS.6.RP.A.3A

Front

What is the formula for finding a missing value in a proportion?

Back

If a/b = c/d, then ad = bc.

Tags

CCSS.7.G.A.1

Front

How can you check if two fractions are equivalent?

Back

Cross-multiply and see if the products are equal.

Tags

CCSS.3.NF.A.3A

CCSS.3.NF.A.3B

CCSS.4.NF.A.1

Front

What is the relationship between ratios and proportions?

Back

Ratios compare two quantities, while proportions state that two ratios are equal.

Tags

CCSS.6.RP.A.3A

Front

If a recipe calls for 2 cups of flour for every 3 cups of sugar, what is the ratio of flour to sugar?

Back

The ratio of flour to sugar is 2:3.

Tags

CCSS.6.RP.A.1

CCSS.6.RP.A.2

Front

How do you convert a ratio into a fraction?

Back

Write the first quantity as the numerator and the second quantity as the denominator.

Tags

CCSS.6.RP.A.1

CCSS.6.RP.A.2