Subtract 20/81 from 1/5
1/5 - 20/81 is -19/405.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 81 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 5 × 81 = 405,
1/5 = 1 × 81/5 × 81 = 81/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
20/81 = 20 × 5/81 × 5 = 100/405 - Subtract the two like fractions:
81/405 - 100/405 = 81 - 100/405 = -19/405
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