Subtract 20/25 from 21/27
21/27 - 20/25 is -1/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 25 is 675
Next, find the equivalent fraction of both fractional numbers with denominator 675 - For the 1st fraction, since 27 × 25 = 675,
21/27 = 21 × 25/27 × 25 = 525/675 - Likewise, for the 2nd fraction, since 25 × 27 = 675,
20/25 = 20 × 27/25 × 27 = 540/675 - Subtract the two like fractions:
525/675 - 540/675 = 525 - 540/675 = -15/675 - After reducing the fraction, the answer is -1/45
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