Subtract 30/81 from 6/21
6/21 - 30/81 is -16/189.
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,
6/21 = 6 × 27/21 × 27 = 162/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
30/81 = 30 × 7/81 × 7 = 210/567 - Subtract the two like fractions:
162/567 - 210/567 = 162 - 210/567 = -48/567 - After reducing the fraction, the answer is -16/189
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