Subtract 15/7 from 18/27
1st number: 18/27, 2nd number: 2 1/7
18/27 - 15/7 is -31/21.
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,
18/27 = 18 × 7/27 × 7 = 126/189 - Likewise, for the 2nd fraction, since 7 × 27 = 189,
15/7 = 15 × 27/7 × 27 = 405/189 - Subtract the two like fractions:
126/189 - 405/189 = 126 - 405/189 = -279/189 - After reducing the fraction, the answer is -31/21
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