Subtract 21/70 from 15/56
15/56 - 21/70 is -9/280.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 70 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 56 × 5 = 280,
15/56 = 15 × 5/56 × 5 = 75/280 - Likewise, for the 2nd fraction, since 70 × 4 = 280,
21/70 = 21 × 4/70 × 4 = 84/280 - Subtract the two like fractions:
75/280 - 84/280 = 75 - 84/280 = -9/280
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