Mathematics 9709 · AS & A Level · Sampling and estimation
Sampling and estimation — practice question
A pet shop is offering $9$ rabbits, and $6$ of them are white. Two rabbits are picked at random without replacement.
(i)[2]
Show that the probability that exactly one of the two rabbits selected is white is $\frac{1}{2}$.
(ii)[3]
Complete the probability distribution table for the number of white rabbits in the sample.
(iii)[1]
Find the expected value of the number of white rabbits in the sample.
Worked solution & mark scheme
This 6-mark question has a full step-by-step worked solution and mark scheme. One marking point: “A correct probability expression, for example $P(W)=\dfrac{6}{9}\times\dfrac{3}{8}+\dfrac{3}{9}\times\dfrac{6}{8}$” …