Subtract 42/27 from 21/20
1st number: 1 1/20, 2nd number: 1 15/27
21/20 - 42/27 is -91/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 27 is 540
Next, find the equivalent fraction of both fractional numbers with denominator 540 - For the 1st fraction, since 20 × 27 = 540,
21/20 = 21 × 27/20 × 27 = 567/540 - Likewise, for the 2nd fraction, since 27 × 20 = 540,
42/27 = 42 × 20/27 × 20 = 840/540 - Subtract the two like fractions:
567/540 - 840/540 = 567 - 840/540 = -273/540 - After reducing the fraction, the answer is -91/180
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