Subtract 81/7 from 40/15
1st number: 2 10/15, 2nd number: 11 4/7
40/15 - 81/7 is -187/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 7 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
40/15 = 40 × 7/15 × 7 = 280/105 - Likewise, for the 2nd fraction, since 7 × 15 = 105,
81/7 = 81 × 15/7 × 15 = 1215/105 - Subtract the two like fractions:
280/105 - 1215/105 = 280 - 1215/105 = -935/105 - After reducing the fraction, the answer is -187/21
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