Subtract 20/81 from 4/36
4/36 - 20/81 is -11/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 81 is 324
Next, find the equivalent fraction of both fractional numbers with denominator 324 - For the 1st fraction, since 36 × 9 = 324,
4/36 = 4 × 9/36 × 9 = 36/324 - Likewise, for the 2nd fraction, since 81 × 4 = 324,
20/81 = 20 × 4/81 × 4 = 80/324 - Subtract the two like fractions:
36/324 - 80/324 = 36 - 80/324 = -44/324 - After reducing the fraction, the answer is -11/81
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