Subtract 21/20 from 28/27
1st number: 1 1/27, 2nd number: 1 1/20
28/27 - 21/20 is -7/540.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 20 is 540
Next, find the equivalent fraction of both fractional numbers with denominator 540 - For the 1st fraction, since 27 × 20 = 540,
28/27 = 28 × 20/27 × 20 = 560/540 - Likewise, for the 2nd fraction, since 20 × 27 = 540,
21/20 = 21 × 27/20 × 27 = 567/540 - Subtract the two like fractions:
560/540 - 567/540 = 560 - 567/540 = -7/540
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