How Do You Convert a Percentage to a Ratio?

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To convert a percentage to a ratio, write out the percentage number as a fraction, reduce the fraction to its simplest form and convert the new fraction to a ratio by replacing the slash mark with a colon. Converting a percentage to a ratio takes only a few minutes and requires paper and a pencil.

  1. Write the percentage down as a fraction

    Start by writing out the percentage as a fraction over 100. So, if the percentage is 46 percent, write it as the following: 46/100.

  2. Reduce the fraction

    Take the fraction down to its simplest form. The example, 46/100, can be reduced by dividing both numbers by 2, or 2/2. This yields the fraction 23/50, which cannot be reduced further.

  3. Express the fraction as a ratio

    Expressing a fraction as a ratio simply means replacing the slash mark with a colon. So, in the example, 23/50 becomes the ratio 23:50.

  4. Convert a ratio into a fraction

    To reverse the process, turn the ratio back into a fraction. To use a new example, convert the ratio 5:7 into 5/7. Divide the top number by the bottom number. In the example, this yields 0.71. Convert the decimal into a percentage by moving the period two places to the right and adding the percent symbol. In this case, the answer is 71 percent, or 71 percent.