Subtract 3/7 from 20/81
20/81 - 3/7 is -103/567.
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,
20/81 = 20 × 7/81 × 7 = 140/567 - Likewise, for the 2nd fraction, since 7 × 81 = 567,
3/7 = 3 × 81/7 × 81 = 243/567 - Subtract the two like fractions:
140/567 - 243/567 = 140 - 243/567 = -103/567
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