Subtract 90/81 from 1/70
1st number: 1/70, 2nd number: 1 9/81
1/70 - 90/81 is -691/630.
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,
1/70 = 1 × 81/70 × 81 = 81/5670 - Likewise, for the 2nd fraction, since 81 × 70 = 5670,
90/81 = 90 × 70/81 × 70 = 6300/5670 - Subtract the two like fractions:
81/5670 - 6300/5670 = 81 - 6300/5670 = -6219/5670 - After reducing the fraction, the answer is -691/630
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