Subtract 3/21 from 42/56
42/56 - 3/21 is 17/28.
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,
42/56 = 42 × 3/56 × 3 = 126/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
3/21 = 3 × 8/21 × 8 = 24/168 - Subtract the two like fractions:
126/168 - 24/168 = 126 - 24/168 = 102/168 - After reducing the fraction, the answer is 17/28
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