Two independent random variables and have the same density for and otherwise. Then equals
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2 marks, −0.666666666666667StatisticsRandom variables and standard distributionsExpectation and varianceHardabout 3 min
DSE 2014 Question 45: Random variables and standard distributions
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Two independent random variables X and Y have the same density f(x)=c(1+x) for x∈[0,1] and 0 otherwise. Then Var(X+Y) equals (A) 2/9 (B) 13/81 (C) 4/45 (D) 5/18
Also written as: Two independent random variables X and Y have the same density f(x)=c(1+x) for x in [0,1] and 0 otherwise. Then Var(X+Y) equals
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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