What Is the Formula for Calculating Percentages?

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Calculating percentages is found by dividing the part by the whole and multiplying the result by 100. For example, 17 is what percent of 68 can be found by dividing 17 by 68 which equals 0.25. Multiplying 0.25 by 100 equals 25 percent.

Calculating the part when the percent and the whole are known is found by dividing the percent by 100, and multiplying the result times the whole. For example, 60 percent of 80 is found by dividing 60 by 100 which equals 0.6, then multiplying 0.6 times 80 which equals 24.

Calculating the whole when the percent and part are known is found by dividing the percent by 100 and dividing the part by the result.

Dividing the numerator of a fraction by the denominator rewrites a fraction as a decimal. For example, the fraction 3/4 is another way of saying 3 divided by 4, which yields a quotient of .75. Since .75 x 100 = 75, 3/4 = 75 percent. This same answer can also be found by multiplying the fraction by 100 and reducing, since 3/4 x 100 = 300/4, and 300/4 reduces to 75.