Subtract 20/30 from 30/81
30/81 - 20/30 is -8/27.
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,
30/81 = 30 × 10/81 × 10 = 300/810 - Likewise, for the 2nd fraction, since 30 × 27 = 810,
20/30 = 20 × 27/30 × 27 = 540/810 - Subtract the two like fractions:
300/810 - 540/810 = 300 - 540/810 = -240/810 - After reducing the fraction, the answer is -8/27
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