Mathematics 9709 · AS & A Level · Sampling and estimation
Sampling and estimation — practice question
The running times for $57$ athletes over $100$ metres are summarised in the following cumulative frequency table: Time (seconds) $<10.0$, $<10.5$, $<11.0$, $<12.0$, $<12.5$, $<13.5$ with cumulative frequencies $0$, $4$, $10$, $40$, $49$, $57$ respectively.
(i)[1]
State how many athletes completed $100$ metres in a time between $10.5$ and $11.0$ seconds.
(ii)[4]
Draw a histogram on graph paper to show the times taken by these athletes to run $100$ metres.
(iii)[4]
Calculate estimates for the mean and variance of the times taken by these athletes.
Worked solution & mark scheme
This 9-mark question has a full step-by-step worked solution and mark scheme. One marking point: “The correct response is $6$.” …