Subtract 3/81 from 18/20
18/20 - 3/81 is 233/270.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 81 is 1620
Next, find the equivalent fraction of both fractional numbers with denominator 1620 - For the 1st fraction, since 20 × 81 = 1620,
18/20 = 18 × 81/20 × 81 = 1458/1620 - Likewise, for the 2nd fraction, since 81 × 20 = 1620,
3/81 = 3 × 20/81 × 20 = 60/1620 - Subtract the two like fractions:
1458/1620 - 60/1620 = 1458 - 60/1620 = 1398/1620 - After reducing the fraction, the answer is 233/270
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