(a)[3]
Construct the probability distribution table for $X$.
(b)[2]
Given that $\text{E}(X) = 0.25$, determine the value of $\operatorname{Var}(X)$.
Mathematics 9709 · AS & A Level · Discrete random variables
Discrete random variables — practice question
A fair red spinner has edges labelled $1, 2, 2, 3$. A fair blue spinner has edges labelled $-3, -2, -1, -1$. Each spinner is spun once, and the number shown on the edge where each spinner stops is recorded. The random variable $X$ represents the total of the two numbers obtained.
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