Subtract 10/27 from 81/21
1st number: 3 18/21, 2nd number: 10/27
81/21 - 10/27 is 659/189.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 27 is 189
Next, find the equivalent fraction of both fractional numbers with denominator 189 - For the 1st fraction, since 21 × 9 = 189,
81/21 = 81 × 9/21 × 9 = 729/189 - Likewise, for the 2nd fraction, since 27 × 7 = 189,
10/27 = 10 × 7/27 × 7 = 70/189 - Subtract the two like fractions:
729/189 - 70/189 = 729 - 70/189 = 659/189 - In mixed form: 392/189
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