The numbers of books read by 18 students during their summer vacation are listed below:
3, 5, 4, 5, 2, 6, 3, 4, 5, 2, 5, 3, 4, 2, 4, 3, 5, 2
Answer the following.
(a) Prepare a frequency distribution of the data.
(b) Find the current mode of the data and its frequency.
(c) The class teacher wants the number 4 to become the exclusive mode (i.e., the only value occurring most frequently). What is the minimum number of additional students who must each read exactly 4 books so that 4 becomes the mode? Show complete reasoning.