Subtract 81/18 from 70/42
1st number: 1 28/42, 2nd number: 4 9/18
70/42 - 81/18 is -17/6.
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,
70/42 = 70 × 3/42 × 3 = 210/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
81/18 = 81 × 7/18 × 7 = 567/126 - Subtract the two like fractions:
210/126 - 567/126 = 210 - 567/126 = -357/126 - After reducing the fraction, the answer is -17/6
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