Add 28/54 and 21/81
28/54 + 21/81 is 7/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 81 is 162
Next, find the equivalent fraction of both fractional numbers with denominator 162 - For the 1st fraction, since 54 × 3 = 162,
28/54 = 28 × 3/54 × 3 = 84/162 - Likewise, for the 2nd fraction, since 81 × 2 = 162,
21/81 = 21 × 2/81 × 2 = 42/162 - Add the two like fractions:
84/162 + 42/162 = 84 + 42/162 = 126/162 - 126/162 simplified gives 7/9
- So, 28/54 + 21/81 = 7/9
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