Subtract 21/15 from 20/84
1st number: 20/84, 2nd number: 1 6/15
20/84 - 21/15 is -122/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 15 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
20/84 = 20 × 5/84 × 5 = 100/420 - Likewise, for the 2nd fraction, since 15 × 28 = 420,
21/15 = 21 × 28/15 × 28 = 588/420 - Subtract the two like fractions:
100/420 - 588/420 = 100 - 588/420 = -488/420 - After reducing the fraction, the answer is -122/105
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