Subtract 20/81 from 90/21
1st number: 4 6/21, 2nd number: 20/81
90/21 - 20/81 is 2290/567.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 21 × 27 = 567,
90/21 = 90 × 27/21 × 27 = 2430/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
20/81 = 20 × 7/81 × 7 = 140/567 - Subtract the two like fractions:
2430/567 - 140/567 = 2430 - 140/567 = 2290/567 - In mixed form: 422/567
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