Subtract 8/20 from 21/54
21/54 - 8/20 is -1/90.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 20 is 540
Next, find the equivalent fraction of both fractional numbers with denominator 540 - For the 1st fraction, since 54 × 10 = 540,
21/54 = 21 × 10/54 × 10 = 210/540 - Likewise, for the 2nd fraction, since 20 × 27 = 540,
8/20 = 8 × 27/20 × 27 = 216/540 - Subtract the two like fractions:
210/540 - 216/540 = 210 - 216/540 = -6/540 - After reducing the fraction, the answer is -1/90
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