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 find the unit rate?

Back

To find the unit rate, divide the quantity by the number of units. For example, if you spend $40 on 5 pounds of concrete, the unit rate is $40 ÷ 5 = $8 per pound.

Tags

CCSS.6.RP.A.1

CCSS.6.RP.A.2

Front

If 12 ounces of lime are mixed with 10 ounces of water, what is the ratio of lime to water?

Back

The ratio of lime to water is 12:10, which simplifies to 6:5.

Tags

CCSS.6.RP.A.1

CCSS.6.RP.A.2

Front

How do you set up a proportion to solve for an unknown?

Back

Set up a proportion by creating a fraction for each ratio and then cross-multiply to solve for the unknown.

Tags

CCSS.7.RP.A.2C

Front

If a store sees 120 customers in 8 hours, how many customers do they see per hour?

Back

They see 120 ÷ 8 = 15 customers per hour.

Tags

CCSS.6.RP.A.1

CCSS.6.RP.A.2

Front

What is the formula to find the total number of customers based on hours worked?

Back

Total customers = (customers per hour) × (number of hours).

Tags

CCSS.7.RP.A.2C

Front

If you paid $15 for 6 gallons of gasoline, what is the cost per gallon?

Back

The cost per gallon is $15 ÷ 6 = $2.50 per gallon.

Tags

CCSS.6.RP.A.1

CCSS.6.RP.A.2

Front

How many gallons of gasoline can you buy with $80 if the cost per gallon is $2.50?

Back

You can buy $80 ÷ $2.50 = 32 gallons.

Tags

CCSS.6.NS.B.3

Front

What is the relationship between lifeguards and swimmers in the given scenario?

Back

The ratio of lifeguards to swimmers is 3:40.

Front

If there are 12 lifeguards on duty, how many swimmers are there?

Back

Using the ratio 3:40, if there are 12 lifeguards, then there are (12 lifeguards × 40 swimmers) ÷ 3 lifeguards = 160 swimmers.