Find one number as a percent of another
Divide the first number by the second number. Move the decimal two places to the right and attach a “%” sign.

Example: The number 15 is what percent of 48?

Divide 15 by 48: 15 ÷ 48 = .3125
Move the decimal over two places to the right and add % sign: 31.25%
So, 15 is 31.25% of 48 homes.

Find a given percent of a number
Convert the given percent to a decimal. Multiply the number by that decimal.

Example: What is 62.1% of 205?

Convert 62.1% into a decimal: 0.621
Multiply 205 by 0.621: 205 * 0.621 = 127.305
So, 127.305 is 62.1% of 205.

Find the percent change
Calculate the difference between the first and second numbers. Divide that difference by the first number. Convert the resulting decimal to a percent.

Example: Calculate the percent increase from 150 to 205.

Find the difference: 205 – 150 = 55
Divide difference by starting value: 55 ÷ 150 = 0.3666
Convert decimal to percentage: 36.7%

So, the percent increase is 36.7%.

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