Subtract 21/20 from 42/54
1st number: 42/54, 2nd number: 1 1/20
42/54 - 21/20 is -49/180.
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,
42/54 = 42 × 10/54 × 10 = 420/540 - Likewise, for the 2nd fraction, since 20 × 27 = 540,
21/20 = 21 × 27/20 × 27 = 567/540 - Subtract the two like fractions:
420/540 - 567/540 = 420 - 567/540 = -147/540 - After reducing the fraction, the answer is -49/180
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