Subtract 7/81 from 90/70
1st number: 1 20/70, 2nd number: 7/81
90/70 - 7/81 is 680/567.
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,
90/70 = 90 × 81/70 × 81 = 7290/5670 - Likewise, for the 2nd fraction, since 81 × 70 = 5670,
7/81 = 7 × 70/81 × 70 = 490/5670 - Subtract the two like fractions:
7290/5670 - 490/5670 = 7290 - 490/5670 = 6800/5670 - After reducing the fraction, the answer is 680/567
- In mixed form: 1113/567
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