Subtract 80/70 from 90/81
1st number: 1 9/81, 2nd number: 1 10/70
90/81 - 80/70 is -2/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 70 is 5670
Next, find the equivalent fraction of both fractional numbers with denominator 5670 - For the 1st fraction, since 81 × 70 = 5670,
90/81 = 90 × 70/81 × 70 = 6300/5670 - Likewise, for the 2nd fraction, since 70 × 81 = 5670,
80/70 = 80 × 81/70 × 81 = 6480/5670 - Subtract the two like fractions:
6300/5670 - 6480/5670 = 6300 - 6480/5670 = -180/5670 - After reducing the fraction, the answer is -2/63
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