The marks obtained by 40 students in a Mathematics test are listed below:
12, 35, 56, 78, 45, 67, 89, 23, 49, 52,
60, 73, 81, 95, 38, 44, 53, 69, 71, 62,
14, 28, 33, 47, 51, 59, 65, 77, 83, 90,
6, 18, 25, 31, 42, 57, 68, 74, 80, 88
(i) Organise the data into a grouped frequency distribution using equal class intervals of width 10, beginning with 0–9.
(ii) Draw a histogram of the grouped distribution on graph paper, choosing a suitable scale for both axes.
(iii) Identify the modal class and state its frequency.
(iv) Write the range of the marks.