The steps to calculate a percent of a given number are first converting the percent to a decimal value by dividing it by 100, then multiplying the given number by that decimal value. The steps to calculate what percent one number is of another are to divide the first number by the second number, then multiply by 100 to convert the decimal result to a percentage value.
For example, to calculate what 25 percent of 80 is, first convert 25 percent to a decimal value by dividing by 100. To do this, move the decimal place two places to the left, for a decimal value of 0.25. Next multiply the original number, 80, by the decimal value, 0.25. The result is 20, so 25 percent of 80 is 20.
If starting with the whole numbers and needing to find the percent value, reverse the operation. To calculate what percentage 20 is of 80, first divide 20 by 80. The result is a decimal value of 0.25, which must be multiplied by 100 to convert it to a percentage value. To do this, move the decimal point two spaces to the right. The result is a percentage value of 25, so 20 is 25 percent of 80.