Subtract 12/9 from 81/42
1st number: 1 39/42, 2nd number: 1 3/9
81/42 - 12/9 is 25/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 9 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 42 × 3 = 126,
81/42 = 81 × 3/42 × 3 = 243/126 - Likewise, for the 2nd fraction, since 9 × 14 = 126,
12/9 = 12 × 14/9 × 14 = 168/126 - Subtract the two like fractions:
243/126 - 168/126 = 243 - 168/126 = 75/126 - After reducing the fraction, the answer is 25/42
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