Subtract 80/81 from 45/90
45/90 - 80/81 is -79/162.
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,
45/90 = 45 × 9/90 × 9 = 405/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
80/81 = 80 × 10/81 × 10 = 800/810 - Subtract the two like fractions:
405/810 - 800/810 = 405 - 800/810 = -395/810 - After reducing the fraction, the answer is -79/162
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