Subtract 72/7 from 81/40
1st number: 2 1/40, 2nd number: 10 2/7
81/40 - 72/7 is -2313/280.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 7 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
81/40 = 81 × 7/40 × 7 = 567/280 - Likewise, for the 2nd fraction, since 7 × 40 = 280,
72/7 = 72 × 40/7 × 40 = 2880/280 - Subtract the two like fractions:
567/280 - 2880/280 = 567 - 2880/280 = -2313/280
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