Subtract 81/40 from 12/7
1st number: 1 5/7, 2nd number: 2 1/40
12/7 - 81/40 is -87/280.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 7 × 40 = 280,
12/7 = 12 × 40/7 × 40 = 480/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
81/40 = 81 × 7/40 × 7 = 567/280 - Subtract the two like fractions:
480/280 - 567/280 = 480 - 567/280 = -87/280
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