Add 21/81 and 81/12
1st number: 21/81, 2nd number: 6 9/12
21/81 + 81/12 is 757/108.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 12 is 324
Next, find the equivalent fraction of both fractional numbers with denominator 324 - For the 1st fraction, since 81 × 4 = 324,
21/81 = 21 × 4/81 × 4 = 84/324 - Likewise, for the 2nd fraction, since 12 × 27 = 324,
81/12 = 81 × 27/12 × 27 = 2187/324 - Add the two like fractions:
84/324 + 2187/324 = 84 + 2187/324 = 2271/324 - 2271/324 simplified gives 757/108
- So, 21/81 + 81/12 = 757/108
In mixed form: 71/108
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