Subtract 20/50 from 21/56
21/56 - 20/50 is -1/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 50 is 1400
Next, find the equivalent fraction of both fractional numbers with denominator 1400 - For the 1st fraction, since 56 × 25 = 1400,
21/56 = 21 × 25/56 × 25 = 525/1400 - Likewise, for the 2nd fraction, since 50 × 28 = 1400,
20/50 = 20 × 28/50 × 28 = 560/1400 - Subtract the two like fractions:
525/1400 - 560/1400 = 525 - 560/1400 = -35/1400 - After reducing the fraction, the answer is -1/40
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