Subtract 20/18 from 81/42
1st number: 1 39/42, 2nd number: 1 2/18
81/42 - 20/18 is 103/126.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 18 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 18 × 7 = 126,
20/18 = 20 × 7/18 × 7 = 140/126 - Subtract the two like fractions:
243/126 - 140/126 = 243 - 140/126 = 103/126
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