Subtract 42/21 from 28/54
1st number: 28/54, 2nd number: 2 0/21
28/54 - 42/21 is -40/27.
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,
28/54 = 28 × 7/54 × 7 = 196/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
42/21 = 42 × 18/21 × 18 = 756/378 - Subtract the two like fractions:
196/378 - 756/378 = 196 - 756/378 = -560/378 - After reducing the fraction, the answer is -40/27
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