Subtract 42/49 from 20/42
20/42 - 42/49 is -8/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 49 is 294
Next, find the equivalent fraction of both fractional numbers with denominator 294 - For the 1st fraction, since 42 × 7 = 294,
20/42 = 20 × 7/42 × 7 = 140/294 - Likewise, for the 2nd fraction, since 49 × 6 = 294,
42/49 = 42 × 6/49 × 6 = 252/294 - Subtract the two like fractions:
140/294 - 252/294 = 140 - 252/294 = -112/294 - After reducing the fraction, the answer is -8/21
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