Subtract 20/81 from 28/21
1st number: 1 7/21, 2nd number: 20/81
28/21 - 20/81 is 88/81.
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,
28/21 = 28 × 27/21 × 27 = 756/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
20/81 = 20 × 7/81 × 7 = 140/567 - Subtract the two like fractions:
756/567 - 140/567 = 756 - 140/567 = 616/567 - After reducing the fraction, the answer is 88/81
- In mixed form: 17/81
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