Subtract 81/40 from 21/15
1st number: 1 6/15, 2nd number: 2 1/40
21/15 - 81/40 is -5/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 40 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 40 × 3 = 120,
81/40 = 81 × 3/40 × 3 = 243/120 - Subtract the two like fractions:
168/120 - 243/120 = 168 - 243/120 = -75/120 - After reducing the fraction, the answer is -5/8
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