(a)[3]
Construct the probability distribution table for $X$.
(b)[3]
Find the value of $\mathrm{Var}(X)$.
Mathematics 9709 · AS & A Level · Discrete random variables
Discrete random variables — practice question
A fair four-sided spinner is labelled on its edges 1, 2, 2, 3. A fair three-sided spinner is labelled on its edges $-2$, $-1$, 1. Each spinner is spun, and the number on the edge at which it stops is recorded. The random variable $X$ is the total of the two recorded numbers.
Worked solution & mark scheme
This 6-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Probability distribution table showing the correct scores and at least one probability correct.” …
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