A mixed number is a whole number plus a fraction such as 15 1/10. A percentage is a fraction that is over a standard denominator of 100  80 percent is also 80/100, for example. Changing a percent into a mixed number is just a matter of thinking of the percent as a number over 100 and convert the fraction into a mixed number.
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Convert any percentage that is over 100 into an improper fraction by putting it over a denominator of 100. An improper fraction has a numerator that is larger than the denominator. Percentages such as 101 percent, 125 percent and 148 percent are all improper fractions  101/100, 125/100 and 148/100 respectively.

Divide the numerator by the denominator to get an improper fraction  101 percent becomes 1 and 1/100; 125 percent becomes 1 and 25/100 and and 148 percent becomes 1 and 48/100, all mixed numbers.

Reduce the fractions. Divide the numerator and the denominator by the highest common number that you can. In the examples above, 25/100 reduces to 1/4 because 25 is the largest number that divides into both 25 and 100. Therefore, 125 percent becomes 1 1/4 as a mixed number. 148 percent becomes 1 12/25 as 48 and 100 are both divisible by 4. The first example, 101 percent, remains 1 1/100 because 1 is the highest number divisible into the numerator and the denominator  the fraction cannot be reduced.
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