Subtract 3/7 from 42/81
42/81 - 3/7 is 17/189.
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,
42/81 = 42 × 7/81 × 7 = 294/567 - Likewise, for the 2nd fraction, since 7 × 81 = 567,
3/7 = 3 × 81/7 × 81 = 243/567 - Subtract the two like fractions:
294/567 - 243/567 = 294 - 243/567 = 51/567 - After reducing the fraction, the answer is 17/189
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