Ratios and Proportions

Front

What is a ratio?

Back

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

Front

What is a proportion?

Back

A proportion is an equation that states that two ratios are equal, expressed as 'a/b = c/d'.

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 is the cross-multiplication method?

Back

The cross-multiplication method involves multiplying the numerator of one ratio by the denominator of the other ratio.

Front

If 2/3 = x/12, what is x?

Back

x = 8 (Cross-multiply: 2 * 12 = 3 * x).

Front

What is the scale factor in similar figures?

Back

The scale factor is the ratio of the lengths of corresponding sides of two similar figures.

Front

If a recipe calls for 2 cups of flour for every 3 cups of sugar, what is the ratio of flour to sugar?

Back

The ratio of flour to sugar is 2:3.

Front

What is a unit rate?

Back

A unit rate is a ratio that compares a quantity to one unit of another quantity, such as miles per hour.

Front

If a car travels 150 miles in 3 hours, what is the unit rate?

Back

The unit rate is 50 miles per hour (150 miles / 3 hours).

Front

How do you find equivalent ratios?

Back

To find equivalent ratios, multiply or divide both terms of the ratio by the same non-zero number.