Subtract 21/81 from 25/12, Solve 2 1/12

Subtract 21/81 from 25/12

1^st number: 2 1/12, 2^nd number: 21/81

25/12 - 21/81 is 197/108.

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,
25/12 = 25 × 27/12 × 27 = 675/324
Likewise, for the 2nd fraction, since 81 × 4 = 324,
21/81 = 21 × 4/81 × 4 = 84/324
Subtract the two like fractions:
675/324 - 84/324 = 675 - 84/324 = 591/324
After reducing the fraction, the answer is 197/108
In mixed form: 189/108

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