Subtract 21/8 from 18/15
1st number: 1 3/15, 2nd number: 2 5/8
18/15 - 21/8 is -57/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 8 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 15 × 8 = 120,
18/15 = 18 × 8/15 × 8 = 144/120 - Likewise, for the 2nd fraction, since 8 × 15 = 120,
21/8 = 21 × 15/8 × 15 = 315/120 - Subtract the two like fractions:
144/120 - 315/120 = 144 - 315/120 = -171/120 - After reducing the fraction, the answer is -57/40
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