Add 21/9 and 81/12
1st number: 2 3/9, 2nd number: 6 9/12
21/9 + 81/12 is 109/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 12 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 9 × 4 = 36,
21/9 = 21 × 4/9 × 4 = 84/36 - Likewise, for the 2nd fraction, since 12 × 3 = 36,
81/12 = 81 × 3/12 × 3 = 243/36 - Add the two like fractions:
84/36 + 243/36 = 84 + 243/36 = 327/36 - 327/36 simplified gives 109/12
- So, 21/9 + 81/12 = 109/12
In mixed form: 91/12
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