Subtract 10/30 from 18/81
18/81 - 10/30 is -1/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 30 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 81 × 10 = 810,
18/81 = 18 × 10/81 × 10 = 180/810 - Likewise, for the 2nd fraction, since 30 × 27 = 810,
10/30 = 10 × 27/30 × 27 = 270/810 - Subtract the two like fractions:
180/810 - 270/810 = 180 - 270/810 = -90/810 - After reducing the fraction, the answer is -1/9
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