Subtract 8/81 from 21/30
21/30 - 8/81 is 487/810.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 81 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 30 × 27 = 810,
21/30 = 21 × 27/30 × 27 = 567/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
8/81 = 8 × 10/81 × 10 = 80/810 - Subtract the two like fractions:
567/810 - 80/810 = 567 - 80/810 = 487/810
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