Subtract 20/81 from 18/15
1st number: 1 3/15, 2nd number: 20/81
18/15 - 20/81 is 386/405.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 81 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 15 × 27 = 405,
18/15 = 18 × 27/15 × 27 = 486/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
20/81 = 20 × 5/81 × 5 = 100/405 - Subtract the two like fractions:
486/405 - 100/405 = 486 - 100/405 = 386/405
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