Subtract 1/5 from 15/81
15/81 - 1/5 is -2/135.
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,
15/81 = 15 × 5/81 × 5 = 75/405 - Likewise, for the 2nd fraction, since 5 × 81 = 405,
1/5 = 1 × 81/5 × 81 = 81/405 - Subtract the two like fractions:
75/405 - 81/405 = 75 - 81/405 = -6/405 - After reducing the fraction, the answer is -2/135
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