Add 21/81 and 12/9
1st number: 21/81, 2nd number: 1 3/9
21/81 + 12/9 is 43/27.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 9 is 81
Next, find the equivalent fraction of both fractional numbers with denominator 81 - For the 1st fraction, since 81 × 1 = 81,
21/81 = 21 × 1/81 × 1 = 21/81 - Likewise, for the 2nd fraction, since 9 × 9 = 81,
12/9 = 12 × 9/9 × 9 = 108/81 - Add the two like fractions:
21/81 + 108/81 = 21 + 108/81 = 129/81 - 129/81 simplified gives 43/27
- So, 21/81 + 12/9 = 43/27
In mixed form: 116/27
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