Subtract 42/56 from 21/49
21/49 - 42/56 is -9/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 56 is 392
Next, find the equivalent fraction of both fractional numbers with denominator 392 - For the 1st fraction, since 49 × 8 = 392,
21/49 = 21 × 8/49 × 8 = 168/392 - Likewise, for the 2nd fraction, since 56 × 7 = 392,
42/56 = 42 × 7/56 × 7 = 294/392 - Subtract the two like fractions:
168/392 - 294/392 = 168 - 294/392 = -126/392 - After reducing the fraction, the answer is -9/28
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