Subtract 90/81 from 3/12
1st number: 3/12, 2nd number: 1 9/81
3/12 - 90/81 is -31/36.
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,
90/81 = 90 × 4/81 × 4 = 360/324 - Subtract the two like fractions:
81/324 - 360/324 = 81 - 360/324 = -279/324 - After reducing the fraction, the answer is -31/36
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