Subtract 84/81 from 4/21
1st number: 4/21, 2nd number: 1 3/81
4/21 - 84/81 is -160/189.
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,
4/21 = 4 × 27/21 × 27 = 108/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
84/81 = 84 × 7/81 × 7 = 588/567 - Subtract the two like fractions:
108/567 - 588/567 = 108 - 588/567 = -480/567 - After reducing the fraction, the answer is -160/189
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