CDF from grouped data

Draw or construct a cumulative frequency graph from grouped data presented in a frequency table.

1 questions

CAIE S1 2017 November Q2
2 The circumferences, \(c \mathrm {~cm}\), of some trees in a wood were measured. The results are summarised in the table.
Circumference \(( c \mathrm {~cm} )\)\(40 < c \leqslant 50\)\(50 < c \leqslant 80\)\(80 < c \leqslant 100\)\(100 < c \leqslant 120\)
Frequency1448708
  1. On the grid, draw a cumulative frequency graph to represent the information.
    \includegraphics[max width=\textwidth, alt={}, center]{9c23b94b-e573-4e13-be90-e63a0daf18e5-03_1401_1404_854_413}
  2. Estimate the percentage of trees which have a circumference larger than 75 cm .