To determine the percentage of a number, divide the fraction of the amount by the whole amount, and multiply the result by 100. As AAA Math explains, to calculate what percentage 68 is of 87, divide 68 by 87; This equals approximately 0.7816. Multiply this answer by 100. The final answer is 78.16 percent.
Dictionary.com defines a percent as one-hundredth of a part. A percentage is how many hundredths of a part a given value is. When dividing the fraction of an amount by the whole amount, the answer results in a decimal. The first column to the right of the decimal is the tenths value, and the column to the right of that is the hundredths value.
Since the answer to the question of percentage has the value of hundredths, multiplying by 100 brings hundredths into the ones column. For example, to determine the percentage value of 25 out of 100, first divide 25 by 100, resulting in 0.25. Multiply by 100 to find the percentage, which in this case is 25 percent. Since the whole value being worked with is 100, the fraction amount is the same as the percentage. Using the same method, to determine the percentage of 1/4, divide 1 by 4, then multiply by 100 for an answer of 25 percent.