Subtract 9/20 from 21/56
21/56 - 9/20 is -3/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 20 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 56 × 5 = 280,
21/56 = 21 × 5/56 × 5 = 105/280 - Likewise, for the 2nd fraction, since 20 × 14 = 280,
9/20 = 9 × 14/20 × 14 = 126/280 - Subtract the two like fractions:
105/280 - 126/280 = 105 - 126/280 = -21/280 - After reducing the fraction, the answer is -3/40
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