Mathematics 9709 · AS & A Level · Sampling and estimation
Sampling and estimation — practice question
On last Saturday, 200 drivers who arrived at a car park were asked how many minutes it had taken them to travel from home to the car park. The outcomes are shown in this cumulative frequency table: Time $t$ (minutes): $t \leq 10$, $t \leq 20$, $t \leq 30$, $t \leq 50$, $t \leq 70$, $t \leq 90$ with cumulative frequencies $16, 50, 106, 146, 176, 200$ respectively.
(i)[2]
Use the grid to draw a cumulative frequency graph for the data.
(ii)[1]
Use the graph to estimate the median of the data.
(iii)[2]
The time taken by $80$ of the drivers was at least $T$ minutes. Use the graph to estimate $T$.
(iv)[4]
Calculate an estimate for the mean time taken by all $200$ drivers to travel to the car park.
Worked solution & mark scheme
This 9-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Axes labelled correctly with suitable scales” …