Subtract 21/27 from 7/20
7/20 - 21/27 is -77/180.
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,
7/20 = 7 × 27/20 × 27 = 189/540 - Likewise, for the 2nd fraction, since 27 × 20 = 540,
21/27 = 21 × 20/27 × 20 = 420/540 - Subtract the two like fractions:
189/540 - 420/540 = 189 - 420/540 = -231/540 - After reducing the fraction, the answer is -77/180
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