Subtract 21/40 from 7/49
7/49 - 21/40 is -107/280.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 40 is 1960
Next, find the equivalent fraction of both fractional numbers with denominator 1960 - For the 1st fraction, since 49 × 40 = 1960,
7/49 = 7 × 40/49 × 40 = 280/1960 - Likewise, for the 2nd fraction, since 40 × 49 = 1960,
21/40 = 21 × 49/40 × 49 = 1029/1960 - Subtract the two like fractions:
280/1960 - 1029/1960 = 280 - 1029/1960 = -749/1960 - After reducing the fraction, the answer is -107/280
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