Subtract 20/25 from 21/28
21/28 - 20/25 is -1/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 25 is 700
Next, find the equivalent fraction of both fractional numbers with denominator 700 - For the 1st fraction, since 28 × 25 = 700,
21/28 = 21 × 25/28 × 25 = 525/700 - Likewise, for the 2nd fraction, since 25 × 28 = 700,
20/25 = 20 × 28/25 × 28 = 560/700 - Subtract the two like fractions:
525/700 - 560/700 = 525 - 560/700 = -35/700 - After reducing the fraction, the answer is -1/20
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