Solving Proportions

Front

What is a proportion?

Back

A proportion is an equation that states that two ratios are equal.

Front

If the ratio of boys to girls is 3 to 2, how can you find the number of girls if there are 12 boys?

Back

Set up the proportion: 3/2 = 12/x. Cross-multiply to find x, which is 8.

Front

What does it mean for two ratios to be proportional?

Back

Two ratios are proportional if they can be expressed as equivalent fractions.

Front

How do you solve a proportion?

Back

To solve a proportion, cross-multiply and then solve for the unknown variable.

Front

If there are 5 boys for every 7 girls, how many boys are there if there are 35 girls?

Back

Set up the proportion: 5/7 = x/35. Cross-multiply to find x, which is 25.

Front

What is the relationship between ratios and fractions?

Back

Ratios can be expressed as fractions, and equivalent ratios correspond to equivalent fractions.

Front

If Sarah used 9 red beads and 12 blue beads, what is the ratio of red to blue beads?

Back

The ratio of red to blue beads is 9:12, which simplifies to 3:4.

Front

How can you find the number of ice cream cones sold if there are 5 cones for every 3 brownies and 24 brownies were sold?

Back

Set up the proportion: 5/3 = x/24. Cross-multiply to find x, which is 40.

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 simplify a ratio?

Back

To simplify a ratio, divide both terms by their greatest common divisor.