Subtract 21/15 from 12/28
1st number: 12/28, 2nd number: 1 6/15
12/28 - 21/15 is -34/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 15 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 28 × 15 = 420,
12/28 = 12 × 15/28 × 15 = 180/420 - Likewise, for the 2nd fraction, since 15 × 28 = 420,
21/15 = 21 × 28/15 × 28 = 588/420 - Subtract the two like fractions:
180/420 - 588/420 = 180 - 588/420 = -408/420 - After reducing the fraction, the answer is -34/35
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