Subtract 21/56 from 3/40
3/40 - 21/56 is -3/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 56 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
3/40 = 3 × 7/40 × 7 = 21/280 - Likewise, for the 2nd fraction, since 56 × 5 = 280,
21/56 = 21 × 5/56 × 5 = 105/280 - Subtract the two like fractions:
21/280 - 105/280 = 21 - 105/280 = -84/280 - After reducing the fraction, the answer is -3/10
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