Subtract 18/9 from 20/81
1st number: 20/81, 2nd number: 2 0/9
20/81 - 18/9 is -142/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 9 is 81
Next, find the equivalent fraction of both fractional numbers with denominator 81 - For the 1st fraction, since 81 × 1 = 81,
20/81 = 20 × 1/81 × 1 = 20/81 - Likewise, for the 2nd fraction, since 9 × 9 = 81,
18/9 = 18 × 9/9 × 9 = 162/81 - Subtract the two like fractions:
20/81 - 162/81 = 20 - 162/81 = -142/81
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