Subtract 21/49 from 7/42
7/42 - 21/49 is -11/42.
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,
7/42 = 7 × 7/42 × 7 = 49/294 - Likewise, for the 2nd fraction, since 49 × 6 = 294,
21/49 = 21 × 6/49 × 6 = 126/294 - Subtract the two like fractions:
49/294 - 126/294 = 49 - 126/294 = -77/294 - After reducing the fraction, the answer is -11/42
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