Subtract 2/7 from 18/81
18/81 - 2/7 is -4/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 7 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 81 × 7 = 567,
18/81 = 18 × 7/81 × 7 = 126/567 - Likewise, for the 2nd fraction, since 7 × 81 = 567,
2/7 = 2 × 81/7 × 81 = 162/567 - Subtract the two like fractions:
126/567 - 162/567 = 126 - 162/567 = -36/567 - After reducing the fraction, the answer is -4/63
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