Subtract 81/42 from 45/36
1st number: 1 9/36, 2nd number: 1 39/42
45/36 - 81/42 is -19/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 42 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 36 × 7 = 252,
45/36 = 45 × 7/36 × 7 = 315/252 - Likewise, for the 2nd fraction, since 42 × 6 = 252,
81/42 = 81 × 6/42 × 6 = 486/252 - Subtract the two like fractions:
315/252 - 486/252 = 315 - 486/252 = -171/252 - After reducing the fraction, the answer is -19/28
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