Subtract 18/8 from 21/15
1st number: 1 6/15, 2nd number: 2 2/8
21/15 - 18/8 is -17/20.
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,
21/15 = 21 × 8/15 × 8 = 168/120 - Likewise, for the 2nd fraction, since 8 × 15 = 120,
18/8 = 18 × 15/8 × 15 = 270/120 - Subtract the two like fractions:
168/120 - 270/120 = 168 - 270/120 = -102/120 - After reducing the fraction, the answer is -17/20
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