Mathematics 9709 · AS & A Level · Sampling and estimation
Sampling and estimation — practice question
For a dental appointment, the chance of waiting for under 5 minutes is 0.16, and the chance of waiting for under 10 minutes is 0.88.
(i)[1]
Find the probability of a waiting time between 5 and 10 minutes.
(ii)[5]
A random sample of 180 people visiting the dentist is selected. Use a suitable approximation to find the probability that more than 115 of these people wait between 5 and 10 minutes.
Worked solution & mark scheme
This 6-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Correct probability $0.72$” …