Proportions

Front

What is a proportion?

Back

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

Front

If 14 sticks of pepperoni are needed for 28 pizzas, how many sticks are needed for 1 pizza?

Back

1 stick of pepperoni is needed for 2 pizzas.

Front

How do you find a missing value in a proportion?

Back

Cross-multiply the known values and solve for the unknown.

Front

Back

x = 28

Front

If hamburger meat costs $6 for 3 pounds, what is the cost per pound?

Back

The cost per pound is $2.

Front

If Janet orders 3 pizzas for every 20 people, how many pizzas are needed for 100 people?

Back

15 pizzas are needed.

Front

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

Back

Front

If 18 pizzas were delivered and Janet orders 3 pizzas for every 20 people, how many people were at the party?

Back

120 people were at the party.

Front

Back

x = 3.

Front

What is the relationship between ratios and proportions?

Back

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