(i)[4]
Draw the probability distribution table for $X$.
(ii)[3]
Find the value of $\mathrm{Var}(X)$.
Mathematics 9709 · AS & A Level · The Poisson distribution
The Poisson distribution — practice question
A fair red spinner has four faces labelled $1, 2, 3, 3$. A fair blue spinner has three faces labelled $-1, 0, 2$. The score from a spinner is the number on the face it lands on. Both spinners are spun simultaneously. The random variable $X$ represents the red spinner score minus the blue spinner score.
Worked solution & mark scheme
This 7-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Probability table listing the correct $x$ values and at least one right probability” …
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