Subtract 2/5 from 20/81
20/81 - 2/5 is -62/405.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 5 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 81 × 5 = 405,
20/81 = 20 × 5/81 × 5 = 100/405 - Likewise, for the 2nd fraction, since 5 × 81 = 405,
2/5 = 2 × 81/5 × 81 = 162/405 - Subtract the two like fractions:
100/405 - 162/405 = 100 - 162/405 = -62/405
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