Subtract 21/54 from 7/20
7/20 - 21/54 is -7/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 54 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 54 × 10 = 540,
21/54 = 21 × 10/54 × 10 = 210/540 - Subtract the two like fractions:
189/540 - 210/540 = 189 - 210/540 = -21/540 - After reducing the fraction, the answer is -7/180
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