Subtract 18/27 from 3/7
3/7 - 18/27 is -5/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 27 is 189
Next, find the equivalent fraction of both fractional numbers with denominator 189 - For the 1st fraction, since 7 × 27 = 189,
3/7 = 3 × 27/7 × 27 = 81/189 - Likewise, for the 2nd fraction, since 27 × 7 = 189,
18/27 = 18 × 7/27 × 7 = 126/189 - Subtract the two like fractions:
81/189 - 126/189 = 81 - 126/189 = -45/189 - After reducing the fraction, the answer is -5/21
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