Subtract 72/81 from 18/30
18/30 - 72/81 is -13/45.
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,
18/30 = 18 × 27/30 × 27 = 486/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
72/81 = 72 × 10/81 × 10 = 720/810 - Subtract the two like fractions:
486/810 - 720/810 = 486 - 720/810 = -234/810 - After reducing the fraction, the answer is -13/45
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