Subtract 21/81 from 5/36
5/36 - 21/81 is -13/108.
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,
5/36 = 5 × 9/36 × 9 = 45/324 - Likewise, for the 2nd fraction, since 81 × 4 = 324,
21/81 = 21 × 4/81 × 4 = 84/324 - Subtract the two like fractions:
45/324 - 84/324 = 45 - 84/324 = -39/324 - After reducing the fraction, the answer is -13/108
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