(i)[2]
Calculate $P(X < 2)$.
(ii)[3]
Calculate the variance of $X$.
(iii)[1]
Determine the value of $a$ such that $P(-a \leq X \leq 2a) = \frac{17}{35}$.
Mathematics 9709 · AS & A Level · Continuous random variables
Continuous random variables — practice question
The random variable $X$ may take the 8 integer values in the set $\{-2, -1, 0, 1, 2, 3, 4, 5\}$. The chance that $X$ equals $0$ is $\frac{1}{10}$. Every other value of $X$ has the same probability.
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