Subtract 81/40 from 12/30
1st number: 12/30, 2nd number: 2 1/40
12/30 - 81/40 is -13/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 30 × 4 = 120,
12/30 = 12 × 4/30 × 4 = 48/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
81/40 = 81 × 3/40 × 3 = 243/120 - Subtract the two like fractions:
48/120 - 243/120 = 48 - 243/120 = -195/120 - After reducing the fraction, the answer is -13/8
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