Subtract 42/7 from 81/20
1st number: 4 1/20, 2nd number: 6 0/7
81/20 - 42/7 is -39/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 7 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
81/20 = 81 × 7/20 × 7 = 567/140 - Likewise, for the 2nd fraction, since 7 × 20 = 140,
42/7 = 42 × 20/7 × 20 = 840/140 - Subtract the two like fractions:
567/140 - 840/140 = 567 - 840/140 = -273/140 - After reducing the fraction, the answer is -39/20
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