Subtract 28/21 from 15/12
1st number: 1 3/12, 2nd number: 1 7/21
15/12 - 28/21 is -1/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
15/12 = 15 × 7/12 × 7 = 105/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
28/21 = 28 × 4/21 × 4 = 112/84 - Subtract the two like fractions:
105/84 - 112/84 = 105 - 112/84 = -7/84 - After reducing the fraction, the answer is -1/12
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