Rates, Ratios, proportions and percents

Front

What is a ratio?

Back

A ratio is a comparison of two quantities by division, showing how many times one value contains or is contained within the other.

Front

What is a proportion?

Back

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

Front

How do you convert a fraction to a percent?

Back

To convert a fraction to a percent, divide the numerator by the denominator and then multiply by 100.

Front

What is the formula to find a percent of a number?

Back

To find a percent of a number, multiply the number by the percent (in decimal form). For example, to find 20% of 50, calculate 50 * 0.20.

Front

If 3/4 of a pizza is left, what percent of the pizza is left?

Back

75% of the pizza is left.

Front

What is the relationship between ratios and proportions?

Back

Ratios compare two quantities, while proportions show that two ratios are equivalent.

Front

How do you find the unit rate?

Back

To find the unit rate, divide the quantity by the number of units. For example, if you buy 10 apples for $5, the unit rate is $5/10 = $0.50 per apple.

Front

What is 25% of 200?

Back

25% of 200 is 50.

Front

If a recipe calls for 2 cups of flour and you want to make half the recipe, how much flour do you need?

Back

You need 1 cup of flour.

Front

What is the percent increase if a price goes from $20 to $25?

Back

The percent increase is 25%.