Subtract 81/36 from 18/42
1st number: 18/42, 2nd number: 2 9/36
18/42 - 81/36 is -51/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 36 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 42 × 6 = 252,
18/42 = 18 × 6/42 × 6 = 108/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
81/36 = 81 × 7/36 × 7 = 567/252 - Subtract the two like fractions:
108/252 - 567/252 = 108 - 567/252 = -459/252 - After reducing the fraction, the answer is -51/28
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