Subtract 15/81 from 5/90
5/90 - 15/81 is -7/54.
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,
5/90 = 5 × 9/90 × 9 = 45/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
15/81 = 15 × 10/81 × 10 = 150/810 - Subtract the two like fractions:
45/810 - 150/810 = 45 - 150/810 = -105/810 - After reducing the fraction, the answer is -7/54
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