Subtract 30/81 from 3/12
3/12 - 30/81 is -13/108.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 81 is 324
Next, find the equivalent fraction of both fractional numbers with denominator 324 - For the 1st fraction, since 12 × 27 = 324,
3/12 = 3 × 27/12 × 27 = 81/324 - Likewise, for the 2nd fraction, since 81 × 4 = 324,
30/81 = 30 × 4/81 × 4 = 120/324 - Subtract the two like fractions:
81/324 - 120/324 = 81 - 120/324 = -39/324 - After reducing the fraction, the answer is -13/108
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