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Questions › JNU › JNU SIS 2015 › Q22
2 marks, −1Statistics › Random variables and standard distributions › Expectation and varianceEasyabout 1 min

JNU SIS 2015 Question 22: Random variables and standard distributions

The random variable XXX takes values 0, 1 and 2 with Pr⁡{X=0}=Pr⁡{X=2}=p\Pr\{X = 0\} = \Pr\{X = 2\} = pPr{X=0}=Pr{X=2}=p and Pr⁡{X=1}=1−2p\Pr\{X = 1\} = 1 - 2pPr{X=1}=1−2p, where 0≤p≤0⋅50 \le p \le 0 \cdot 50≤p≤0⋅5. For which of the following values of ppp does XXX attain the maximum variance?

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The random variable X takes values 0, 1 and 2 with Pr {X = 0} = Pr {X = 2} = p and Pr {X = 1} = 1 - 2p, where 0 ≤ p ≤ 0 · 5. For which of the following values of p does X attain the maximum variance? (A) 0 (B) 0·3 (C) 0·1 (D) 0·5

Also written as: The random variable X takes values 0, 1 and 2 with Pr {X = 0} = Pr {X = 2} = p and Pr {X = 1} = 1 - 2p, where 0 <= p <= 0 * 5. For which of the following values of p does X attain the maximum variance?

Random variables and standard distributions has come up 173 times in 7 exams since 2005.

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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Question from the JNU SIS 2015 paper. Solutions are TestStop's own. Not affiliated with or endorsed by any examination authority.