Subtract 15/28 from 21/56
21/56 - 15/28 is -9/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 28 is 56
Next, find the equivalent fraction of both fractional numbers with denominator 56 - For the 1st fraction, since 56 × 1 = 56,
21/56 = 21 × 1/56 × 1 = 21/56 - Likewise, for the 2nd fraction, since 28 × 2 = 56,
15/28 = 15 × 2/28 × 2 = 30/56 - Subtract the two like fractions:
21/56 - 30/56 = 21 - 30/56 = -9/56
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