Subtract 42/49 from 7/20
7/20 - 42/49 is -71/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 49 is 980
Next, find the equivalent fraction of both fractional numbers with denominator 980 - For the 1st fraction, since 20 × 49 = 980,
7/20 = 7 × 49/20 × 49 = 343/980 - Likewise, for the 2nd fraction, since 49 × 20 = 980,
42/49 = 42 × 20/49 × 20 = 840/980 - Subtract the two like fractions:
343/980 - 840/980 = 343 - 840/980 = -497/980 - After reducing the fraction, the answer is -71/140
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