Subtract 21/12 from 28/56
1st number: 28/56, 2nd number: 1 9/12
28/56 - 21/12 is -5/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 12 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 56 × 3 = 168,
28/56 = 28 × 3/56 × 3 = 84/168 - Likewise, for the 2nd fraction, since 12 × 14 = 168,
21/12 = 21 × 14/12 × 14 = 294/168 - Subtract the two like fractions:
84/168 - 294/168 = 84 - 294/168 = -210/168 - After reducing the fraction, the answer is -5/4
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