Subtract 42/21 from 8/18
1st number: 8/18, 2nd number: 2 0/21
8/18 - 42/21 is -14/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
8/18 = 8 × 7/18 × 7 = 56/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
42/21 = 42 × 6/21 × 6 = 252/126 - Subtract the two like fractions:
56/126 - 252/126 = 56 - 252/126 = -196/126 - After reducing the fraction, the answer is -14/9
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