Subtract 20/81 from 90/7
1st number: 12 6/7, 2nd number: 20/81
90/7 - 20/81 is 7150/567.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 7 × 81 = 567,
90/7 = 90 × 81/7 × 81 = 7290/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
20/81 = 20 × 7/81 × 7 = 140/567 - Subtract the two like fractions:
7290/567 - 140/567 = 7290 - 140/567 = 7150/567 - In mixed form: 12346/567
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