Subtract 56/81 from 72/21
1st number: 3 9/21, 2nd number: 56/81
72/21 - 56/81 is 1552/567.
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,
72/21 = 72 × 27/21 × 27 = 1944/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
56/81 = 56 × 7/81 × 7 = 392/567 - Subtract the two like fractions:
1944/567 - 392/567 = 1944 - 392/567 = 1552/567 - In mixed form: 2418/567
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