Subtract 42/81 from 12/36
12/36 - 42/81 is -5/27.
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,
12/36 = 12 × 9/36 × 9 = 108/324 - Likewise, for the 2nd fraction, since 81 × 4 = 324,
42/81 = 42 × 4/81 × 4 = 168/324 - Subtract the two like fractions:
108/324 - 168/324 = 108 - 168/324 = -60/324 - After reducing the fraction, the answer is -5/27
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