Ratios and Proportions

Front

What is a ratio?

Back

A ratio is a comparison of two quantities by division, expressed as 'a to b' or a:b.

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 relationship between a, b, c, and d?

Back

The relationship is that a times d equals b times c (a*d = b*c).

Front

What is the first step to solve for a missing value in a proportion?

Back

The first step is to cross-multiply the known values.

Front

In the ratio of dogs to cats being 5:3, if there are 25 dogs, how many cats are there?

Back

There are 15 cats.

Front

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

Back

If a/b = c/d, then d = (b*c)/a.

Front

What is the value of k if 1/17 = 1/k?

Back

k = 17.

Front

If 2/3 = x/12, what is the value of x?

Back

x = 8.