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