Subtract 5/21 from 20/56
20/56 - 5/21 is 5/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 56 × 3 = 168,
20/56 = 20 × 3/56 × 3 = 60/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
5/21 = 5 × 8/21 × 8 = 40/168 - Subtract the two like fractions:
60/168 - 40/168 = 60 - 40/168 = 20/168 - After reducing the fraction, the answer is 5/42
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