Mathematics 0580 · IGCSE · Cumulative frequency diagrams
Cumulative frequency diagrams — practice question
Leo recorded the rainfall each day, in millimetres, over 120 days. The cumulative frequency table displays the outcomes. The rainfall classes are $r \leq 20$, $r \leq 25$, $r \leq 35$, $r \leq 40$, $r \leq 60$, $r \leq 70$ with cumulative frequencies 5, 13, 72, 90, 117 and 120.
(a)[3]
On the grid below, sketch a cumulative frequency diagram to represent these results.
(b(i))[1]
State the median.
(b(ii))[2]
Use your diagram to determine the number of days when the rainfall was more than 50 mm.
(c)[2]
Use the information in the cumulative frequency table to complete the frequency table below.
(d)[4]
Use your frequency table to work out an estimate of the mean. You must show all your working.
(e)[4]
Calculate the frequency density for the intervals $20 < r \leq 25$, $40 < r \leq 60$ and $60 < r \leq 70$.
Worked solution & mark scheme
This 16-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Fully correct diagram with every point plotted” …