Mathematics 9709 · AS & A Level · Continuous random variables
Continuous random variables — practice question
Each box contains 30 blank CDs. The chance that a blank CD is faulty is 0.04. A box is rejected if more than 2 of the blank CDs are faulty.
(a(i))[3]
Determine the probability that a box is rejected.
(a(ii))[5]
A random sample of 280 boxes is taken. Use an approximation to find the probability that at least 30 of these boxes are rejected.
(ii)[5]
A random total of 280 boxes is selected. Use an approximation to find the probability that at least 30 of these boxes are rejected.
Worked solution & mark scheme
This 13-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Applying the binomial probability method for $P(X>2)$ or the complementary probability” …