Subtract 90/81 from 3/4, Solve 3/4 - 1 9/81 as a fraction

Subtract 90/81 from 3/4

1^st number: 3/4, 2^nd number: 1 9/81

3/4 - 90/81 is -13/36.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 81 is 324

Next, find the equivalent fraction of both fractional numbers with denominator 324
For the 1st fraction, since 4 × 81 = 324,
3/4 = 3 × 81/4 × 81 = 243/324
Likewise, for the 2nd fraction, since 81 × 4 = 324,
90/81 = 90 × 4/81 × 4 = 360/324
Subtract the two like fractions:
243/324 - 360/324 = 243 - 360/324 = -117/324
After reducing the fraction, the answer is -13/36

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