Subtract 24/81 from 18/90
18/90 - 24/81 is -13/135.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 81 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 90 × 9 = 810,
18/90 = 18 × 9/90 × 9 = 162/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
24/81 = 24 × 10/81 × 10 = 240/810 - Subtract the two like fractions:
162/810 - 240/810 = 162 - 240/810 = -78/810 - After reducing the fraction, the answer is -13/135
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