Subtract 15/81 from 7/90
7/90 - 15/81 is -29/270.
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,
7/90 = 7 × 9/90 × 9 = 63/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
15/81 = 15 × 10/81 × 10 = 150/810 - Subtract the two like fractions:
63/810 - 150/810 = 63 - 150/810 = -87/810 - After reducing the fraction, the answer is -29/270
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