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 two ratios and set the products equal to each other.

Front

What is the ratio of sunfish to perch if there are 300 sunfish and 225 perch?

Back

The ratio is 4:3.

Front

If a 12-ounce shampoo bottle lasts 16 weeks, how do you find the duration for an 18-ounce bottle?

Back

Set up a proportion: 12 ounces/16 weeks = 18 ounces/x weeks, then solve for x.

Front

What is the unit rate?

Back

The unit rate is a comparison of any two units in which one of the terms is 1.

Front

If Ramon travels 20 miles in 20 minutes, what is his speed in miles per hour?

Back

His speed is 60 miles per hour.

Front

What is the relationship between ratios and fractions?

Back

Ratios can be expressed as fractions, and vice versa.

Front

If the ratio of boys to girls is 3 to 2 and there are 12 boys, how many girls are there?

Back

There are 8 girls.

Front

How do you find the total amount saved over a period of time if you know the amount saved per week?

Back

Multiply the amount saved per week by the number of weeks.

Front

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

Back

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