Subtract 81/63 from 8/42
1st number: 8/42, 2nd number: 1 18/63
8/42 - 81/63 is -23/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 63 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 42 × 3 = 126,
8/42 = 8 × 3/42 × 3 = 24/126 - Likewise, for the 2nd fraction, since 63 × 2 = 126,
81/63 = 81 × 2/63 × 2 = 162/126 - Subtract the two like fractions:
24/126 - 162/126 = 24 - 162/126 = -138/126 - After reducing the fraction, the answer is -23/21
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