Subtract 2/21 from 4/81
4/81 - 2/21 is -26/567.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 21 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 81 × 7 = 567,
4/81 = 4 × 7/81 × 7 = 28/567 - Likewise, for the 2nd fraction, since 21 × 27 = 567,
2/21 = 2 × 27/21 × 27 = 54/567 - Subtract the two like fractions:
28/567 - 54/567 = 28 - 54/567 = -26/567
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