Subtract 20/30 from 28/81
28/81 - 20/30 is -26/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 30 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 81 × 10 = 810,
28/81 = 28 × 10/81 × 10 = 280/810 - Likewise, for the 2nd fraction, since 30 × 27 = 810,
20/30 = 20 × 27/30 × 27 = 540/810 - Subtract the two like fractions:
280/810 - 540/810 = 280 - 540/810 = -260/810 - After reducing the fraction, the answer is -26/81
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