Subtract 81/40 from 15/20
1st number: 15/20, 2nd number: 2 1/40
15/20 - 81/40 is -51/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 20 × 2 = 40,
15/20 = 15 × 2/20 × 2 = 30/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
81/40 = 81 × 1/40 × 1 = 81/40 - Subtract the two like fractions:
30/40 - 81/40 = 30 - 81/40 = -51/40
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