Subtract 54/81 from 10/21
10/21 - 54/81 is -4/21.
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,
10/21 = 10 × 27/21 × 27 = 270/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
54/81 = 54 × 7/81 × 7 = 378/567 - Subtract the two like fractions:
270/567 - 378/567 = 270 - 378/567 = -108/567 - After reducing the fraction, the answer is -4/21
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