Let Y denote the number of heads obtained when 3 coins are tossed. The variance of is:
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DSE 2007 Question 20: Random variables and standard distributions
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Let Y denote the number of heads obtained when 3 coins are tossed. The variance of Y² is: (A) 6.5 (B) 7.0 (C) 7.5 (D) 8.0
Also written as: Let Y denote the number of heads obtained when 3 coins are tossed. The variance of Y^2 is:
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What this question tests
This question is on Expectation and variance, part of Random variables and standard distributions in Statistics.
The mean and spread of a random variable, and how they change under transformations and sums.
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