Subtract 81/40 from 21/14
1st number: 1 7/14, 2nd number: 2 1/40
21/14 - 81/40 is -21/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 14 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 14 × 20 = 280,
21/14 = 21 × 20/14 × 20 = 420/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
81/40 = 81 × 7/40 × 7 = 567/280 - Subtract the two like fractions:
420/280 - 567/280 = 420 - 567/280 = -147/280 - After reducing the fraction, the answer is -21/40
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