The following data give the repair costs (in RM) for 30 randomly selected cars from a list of cars involved in collisions.
a) By using RM 1 as the lower limit of the first class and RM 1400 as the width of each class, construct a frequency distribution table.
b) Compute the cumulative frequency.
c) Draw a cumulative frequency polygon of the type "less than or equal".
d) From your graph in c), estimate the following:
(ii) first quartile
(iii) third quartile
(iv) inter quartile range