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 variable.

Front

What does it mean to cross-multiply?

Back

Cross-multiplying means 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 3/4 = x/8?

Back

Cross-multiply to get 3*8 = 4*x.

Front

Solve the proportion: 2/3 = x/12.

Back

x = 8.

Front

What is the solution to the proportion 5/x = 15/3?

Back

x = 1.

Front

If 4/5 = x/25, what is x?

Back

x = 20.

Front

What is the value of x in the proportion 7/x = 14/2?

Back

x = 1.

Front

How do you check if your solution to a proportion is correct?

Back

Substitute the value back into the original proportion to see if both sides are equal.