Subtract 90/81 from 7/12
1st number: 7/12, 2nd number: 1 9/81
7/12 - 90/81 is -19/36.
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,
7/12 = 7 × 27/12 × 27 = 189/324 - Likewise, for the 2nd fraction, since 81 × 4 = 324,
90/81 = 90 × 4/81 × 4 = 360/324 - Subtract the two like fractions:
189/324 - 360/324 = 189 - 360/324 = -171/324 - After reducing the fraction, the answer is -19/36
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