Subtract 49/56 from 21/70
21/70 - 49/56 is -23/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 56 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 70 × 4 = 280,
21/70 = 21 × 4/70 × 4 = 84/280 - Likewise, for the 2nd fraction, since 56 × 5 = 280,
49/56 = 49 × 5/56 × 5 = 245/280 - Subtract the two like fractions:
84/280 - 245/280 = 84 - 245/280 = -161/280 - After reducing the fraction, the answer is -23/40
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