Subtract 28/56 from 21/40
21/40 - 28/56 is 1/40.
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,
21/40 = 21 × 7/40 × 7 = 147/280 - Likewise, for the 2nd fraction, since 56 × 5 = 280,
28/56 = 28 × 5/56 × 5 = 140/280 - Subtract the two like fractions:
147/280 - 140/280 = 147 - 140/280 = 7/280 - After reducing the fraction, the answer is 1/40
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