Subtract 21/8 from 15/12
1st number: 1 3/12, 2nd number: 2 5/8
15/12 - 21/8 is -11/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 8 is 24
Next, find the equivalent fraction of both fractional numbers with denominator 24 - For the 1st fraction, since 12 × 2 = 24,
15/12 = 15 × 2/12 × 2 = 30/24 - Likewise, for the 2nd fraction, since 8 × 3 = 24,
21/8 = 21 × 3/8 × 3 = 63/24 - Subtract the two like fractions:
30/24 - 63/24 = 30 - 63/24 = -33/24 - After reducing the fraction, the answer is -11/8
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