Subtract 42/81 from 4/90
4/90 - 42/81 is -64/135.
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,
4/90 = 4 × 9/90 × 9 = 36/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
42/81 = 42 × 10/81 × 10 = 420/810 - Subtract the two like fractions:
36/810 - 420/810 = 36 - 420/810 = -384/810 - After reducing the fraction, the answer is -64/135
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