Subtract 28/21 from 42/54
1st number: 42/54, 2nd number: 1 7/21
42/54 - 28/21 is -5/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 21 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 54 × 7 = 378,
42/54 = 42 × 7/54 × 7 = 294/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
28/21 = 28 × 18/21 × 18 = 504/378 - Subtract the two like fractions:
294/378 - 504/378 = 294 - 504/378 = -210/378 - After reducing the fraction, the answer is -5/9
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