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A die is thrown twice. Obtaining a number greater than 4 is treated as a success. Find the variance of the probability distribution of the number of successes.
- 2/9
- 4/9
- 1/3
- None of these
Correct answer: 4/9
Solution
With p = 1/3 and n = 2, the variance is 2 * (1/3) * (2/3) = 4/9.
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