Subtract 20/81 from 4/21
4/21 - 20/81 is -32/567.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 21 × 27 = 567,
4/21 = 4 × 27/21 × 27 = 108/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
20/81 = 20 × 7/81 × 7 = 140/567 - Subtract the two like fractions:
108/567 - 140/567 = 108 - 140/567 = -32/567
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