Solving 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 variable.

Front

What does cross-multiplication involve?

Back

Cross-multiplication involves multiplying the numerator of one ratio by the denominator of the other ratio.

Front

If a/b = c/d, what is the cross-multiplication result?

Back

The result is a*d = b*c.

Front

What is the first step in solving the proportion 3/x = 6/12?

Back

Cross-multiply to get 3*12 = 6*x.

Front

What is the value of x in the proportion 3/x = 6/12?

Back

x = 8.

Front

What is a unit rate?

Back

A unit rate is a ratio that compares a quantity to one unit of another quantity.

Front

How do you find a unit rate from a proportion?

Back

Divide the numerator by the denominator to find the rate per one unit.

Front

What is an example of a unit rate?

Back

If a car travels 300 miles in 5 hours, the unit rate is 60 miles per hour.

Front

What is the relationship between ratios and proportions?

Back

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