Subtract 12/81 from 21/24
21/24 - 12/81 is 157/216.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 24 and 81 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 24 × 27 = 648,
21/24 = 21 × 27/24 × 27 = 567/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
12/81 = 12 × 8/81 × 8 = 96/648 - Subtract the two like fractions:
567/648 - 96/648 = 567 - 96/648 = 471/648 - After reducing the fraction, the answer is 157/216
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