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, you can use cross multiplication.

Front

What is cross multiplication?

Back

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

Front

If 12 lawnmowers take 8 hours to produce, how many hours does it take to produce 1 lawnmower?

Back

It takes 8/12 hours, or 2/3 hours, to produce 1 lawnmower.

Front

If a lawnmower factory can produce 12 lawnmowers in 8 hours, how many lawnmowers can it produce in 1 hour?

Back

It can produce 12/8 lawnmowers, or 1.5 lawnmowers, in 1 hour.

Front

What is the formula for finding an unknown in a proportion?

Back

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

Front

Are the ratios 3:4 and 6:8 proportional?

Back

Yes, they are proportional because 3/4 = 6/8.

Front

What does it mean if two ratios are not proportional?

Back

It means that the two ratios do not represent the same relationship.

Front

Solve the proportion: 3/4 = x/16.

Back

x = 12.

Front

If 5/8 = x/32, what is x?

Back

x = 20.