Subtract 81/7 from 20/27
1st number: 20/27, 2nd number: 11 4/7
20/27 - 81/7 is -2047/189.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 7 is 189
Next, find the equivalent fraction of both fractional numbers with denominator 189 - For the 1st fraction, since 27 × 7 = 189,
20/27 = 20 × 7/27 × 7 = 140/189 - Likewise, for the 2nd fraction, since 7 × 27 = 189,
81/7 = 81 × 27/7 × 27 = 2187/189 - Subtract the two like fractions:
140/189 - 2187/189 = 140 - 2187/189 = -2047/189
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