Percents and Proportions

Front

What is a percent?

Back

A percent is a ratio expressed as a fraction of 100. It represents how many parts out of 100 are being considered.

Front

How do you calculate a percentage of a number?

Back

To calculate a percentage of a number, multiply the number by the percentage (in decimal form). For example, to find 20% of 50, calculate 50 * 0.20 = 10.

Front

What is a proportion?

Back

A proportion is an equation that states that two ratios are equal. For example, if a/b = c/d, then a, b, c, and d are in proportion.

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. For example, 1/4 = (1 ÷ 4) * 100 = 25%.

Front

What is the formula to find the percent increase?

Back

The formula for percent increase is: ((New Value - Original Value) / Original Value) * 100.

Front

What is the formula to find the percent decrease?

Back

The formula for percent decrease is: ((Original Value - New Value) / Original Value) * 100.

Front

If 700 million Snapchats are sent every day, how many are goofy if 98% are goofy?

Back

686 million Snapchats are goofy (700 million * 0.98 = 686 million).

Front

If 5 is 2% of a number, how do you find that number?

Back

To find the number, divide 5 by 0.02 (5 ÷ 0.02 = 250).

Front

What percent of 28 is 25?

Back

To find the percent, divide 25 by 28 and multiply by 100. (25 ÷ 28) * 100 = 89.3%.

Front

What percent is 30 of 2?

Back

30 is 1500% of 2 (30 ÷ 2 * 100 = 1500%).