Subtract 3/10 from 20/81
20/81 - 3/10 is -43/810.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 10 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 81 × 10 = 810,
20/81 = 20 × 10/81 × 10 = 200/810 - Likewise, for the 2nd fraction, since 10 × 81 = 810,
3/10 = 3 × 81/10 × 81 = 243/810 - Subtract the two like fractions:
200/810 - 243/810 = 200 - 243/810 = -43/810
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