Subtract 70/7 from 81/42
1st number: 1 39/42, 2nd number: 10 0/7
81/42 - 70/7 is -113/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 7 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
81/42 = 81 × 1/42 × 1 = 81/42 - Likewise, for the 2nd fraction, since 7 × 6 = 42,
70/7 = 70 × 6/7 × 6 = 420/42 - Subtract the two like fractions:
81/42 - 420/42 = 81 - 420/42 = -339/42 - After reducing the fraction, the answer is -113/14
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