Subtract 4/81 from 1/21
1/21 - 4/81 is -1/567.
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,
1/21 = 1 × 27/21 × 27 = 27/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
4/81 = 4 × 7/81 × 7 = 28/567 - Subtract the two like fractions:
27/567 - 28/567 = 27 - 28/567 = -1/567
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