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Subtracting fractions from whole numbers isn't as hard as it looks. There are two main ways to go about it: you can either convert the whole number into a fraction, or subtract 1 from that whole number and convert the 1 into a fraction with the same base as the fraction you're subtracting from it. Once you have two fractions with the same base, you can start to subtract. Both methods will help you.
Steps
Method 1
Method 1 of 2:Subtracting Fractions from Whole Numbers

1Convert the whole number to a fraction. To do this, give the whole number a denominator of 1.^{[1] X Research source }
 Example:

2Convert to fractions of like denominators. The original fraction's denominator is also the least common denominator (LCD) of the two fractions. Multiply the top and bottom of the "whole number fraction" by this number so the fractions have the same denominator.^{[2] X Research source }Advertisement

3Subtract the numerators. Now that the fractions have the same denominators, you can treat the numerators as a normal subtraction problem:^{[3] X Research source }
 =

4Convert to a mixed number (optional). If your answer is an improper fraction, you may need to rewrite it as a mixed number:^{[4] X Research source }
 Example: Rewrite as a mixed number.
 How many times does 5 fit evenly into 36? 5 x 7 = 35, so the whole number portion is 7.
 What's left over? The whole number portion is equivalent to , so solve  =
 Combine the whole number and fraction: =
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Method 2
Method 2 of 2:Alternate Method

1Try this for large whole numbers. Did you see how the method above converts the whole number into a fraction, then converts back to a mixed number at the end? This method lets you skip some of that so the fraction only involves smaller numbers.

2Convert improper fractions to mixed numbers. Skip this step if your fraction is not improper. (An improper fraction has a larger number on top than on bottom.)^{[5] X Research source }
 Example:

3Separate the whole number into 1 and another whole number. For example, rewrite 5 as 4 + 1, or rewrite 22 as 21 + 1.

4Convert the 1 into a fraction. At this point we're using the method above to solve the part of the problem in the form "1  (fraction)". The other whole number will stay the same for the rest of the problem.

5Multiply to give the fractions like denominators. As described above, multiply the top and bottom of your new fraction so it has the same denominator as the original fraction.

6Combine the two fractions. Subtract the numerators to solve the fraction part of the equation.Advertisement
Community Q&A

QuestionIf the whole number is 1, then how am I supposed to make it into a fraction if 1/1 is 1 whole?DonaganTop AnswererAs a simple example, let's say we're subtracting ¾ from 1. Convert 1 to 4/4. 4/4  ¾ = ¼. If the whole number is something else, let's say 6, and you're subtracting ¾, convert the 6 to 24/4. 24/4  ¾ = 21/4, or 5¼.

QuestionCan you help me with 5 5/6  2 2/3 step by step?WOOHPCommunity Answer1. 5 5/6  2 2/3 = 5 5/6  2 4/6 2. 5 5/6  2/4/6 = 3 1/6

QuestionI'm confused. Can you please give an example?Karianna WoodCommunity AnswerTake 3  2/7, for example. What over 7 is 3? 21, because 7 x 3 = 21. So 3  2/7 is the same as 21/7  2/7. What is 21/7  3/7? 21  3 = 18. So 21/7  3/7 = 18/7. (Optional) Simplify 18/7, which is 2 4/7. Does that help?

QuestionHow do I subtract 8  1/8?DonaganTop AnswererConvert 8 to 64/8. 64/8  1/8 = 63/8, or 7 7/8.

QuestionHow do I subtract a whole number and a mixed number?Community AnswerSubtract the "number" part of the mixed number (i.e., if it was 2 3/4, then subtract 2), then subtract the fraction.

QuestionHow do I subtract a whole number from a fraction?Community AnswerSubtract it like a natural number. The whole number cannot be in lowest term

QuestionThreeeighths is equal to how many 64ths?Community AnswerThere are 8 sixtyfourths in one eighth, which means there are 3 x 8 or 24 sixtyfourths in threeeighths. 3/8 = 24/64.

QuestionHow do I subtract 2/7 and 1/3 from 1?Community AnswerChange the fractions so that they have equal denominators 6/21 and 7/21 then add the top numbers 6+7=13, so 13/21 then subtract that from 21/21 21/2113/21=8/21.

QuestionHow do I calculate 3 1/7  1/2?DonaganTop AnswererFirst convert the mixed number to an improper fraction. Then convert both fractions to equivalent fractions with like denominators. Then subtract the smaller numerator from the larger numerator, using the new denominator.

QuestionWhat if I have a proper fraction instead?Community AnswerIf you have a proper fraction, you still need to make sure both have the same denominators before adding or subtracting. The LCD rule still applies.
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References
 ↑ http://virtualnerd.com/algebra1/algebrafoundations/realnumberaddsubtract/realnumbersubtract/subtractwholenumberfromfraction
 ↑ https://mathwizz.com/fractions/help/help11.htm
 ↑ https://www.montereyinstitute.org/courses/DevelopmentalMath/TEXTGROUP18_RESOURCE/U02_L3_T2_text_final.html
 ↑ https://www.calculatorsoup.com/calculators/math/mixednumbers.php
 ↑ https://www.mathsisfun.com/improperfractions.html
About This Article
To subtract fractions from whole numbers, convert the whole number to a fraction by putting it over 1. Then, adjust the fractions to have like denominators by multiplying the new fraction by the denominator of the original fraction. Subtract the numerators of the two numbers, and convert the answer to a mixed number if necessary. Remember to reduce the fraction if possible or divide it into a whole number. For a trick to help subtract a fraction from a very large whole number, read on!