Subtract 9/21 from 3/56
3/56 - 9/21 is -3/8.
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,
3/56 = 3 × 3/56 × 3 = 9/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
9/21 = 9 × 8/21 × 8 = 72/168 - Subtract the two like fractions:
9/168 - 72/168 = 9 - 72/168 = -63/168 - After reducing the fraction, the answer is -3/8
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