Subtract 12/15 from 21/56
21/56 - 12/15 is -17/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 15 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 56 × 15 = 840,
21/56 = 21 × 15/56 × 15 = 315/840 - Likewise, for the 2nd fraction, since 15 × 56 = 840,
12/15 = 12 × 56/15 × 56 = 672/840 - Subtract the two like fractions:
315/840 - 672/840 = 315 - 672/840 = -357/840 - After reducing the fraction, the answer is -17/40
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