Proportions

Front

What is a proportion?

Back

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

Front

How do you solve a proportion?

Back

To solve a proportion, cross-multiply the terms and then solve for the unknown.

Front

What is the ratio of boys to girls if there are 12 boys and 8 girls?

Back

The ratio is 3:2.

Front

If 1 pizza feeds 3 people, how many pizzas are needed for 36 people?

Back

12 pizzas.

Front

What is the relationship between ratios and proportions?

Back

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

Front

If a recipe calls for 1.5 cups of milk for every 3 cups of flour, how much milk is needed for 5 cups of flour?

Back

2.5 cups of milk.

Front

How do you find the total cost for a larger group if you know the cost for a smaller group?

Back

Use the unit rate from the smaller group to calculate the total cost for the larger group.

Front

What is the unit rate?

Back

The unit rate is a comparison of any two units, expressed as a quantity of one unit.

Front

If 13 out of 20 homes have a computer, how many homes would you expect to have a computer on a street with 60 homes?

Back

39 homes.

Front

What does it mean if two ratios are equivalent?

Back

It means they represent the same relationship between quantities.