Subtract 20/56 from 3/21
3/21 - 20/56 is -3/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 56 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
3/21 = 3 × 8/21 × 8 = 24/168 - Likewise, for the 2nd fraction, since 56 × 3 = 168,
20/56 = 20 × 3/56 × 3 = 60/168 - Subtract the two like fractions:
24/168 - 60/168 = 24 - 60/168 = -36/168 - After reducing the fraction, the answer is -3/14
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