Subtract 84/81 from 42/70
1st number: 42/70, 2nd number: 1 3/81
42/70 - 84/81 is -59/135.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 81 is 5670
Next, find the equivalent fraction of both fractional numbers with denominator 5670 - For the 1st fraction, since 70 × 81 = 5670,
42/70 = 42 × 81/70 × 81 = 3402/5670 - Likewise, for the 2nd fraction, since 81 × 70 = 5670,
84/81 = 84 × 70/81 × 70 = 5880/5670 - Subtract the two like fractions:
3402/5670 - 5880/5670 = 3402 - 5880/5670 = -2478/5670 - After reducing the fraction, the answer is -59/135
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Related: 84/70-84/81