Add 21/81 and 7/9
21/81 + 7/9 is 28/27.
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,
7/9 = 7 × 9/9 × 9 = 63/81 - Add the two like fractions:
21/81 + 63/81 = 21 + 63/81 = 84/81 - 84/81 simplified gives 28/27
- So, 21/81 + 7/9 = 28/27
In mixed form: 11/27
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