In an examination the following scores were a chief by a group of students: draw a cumulative frequency graph of the data and use it to find:
a) The median examination mark.
b) How many students score less than 65 marks
c) How many students scored between 50 and 80 marks
d) How many students failed, given that the pass mark is 50
e) The credit mark, mark given that the top 25% of students were awarded credits
f) The interquartile range.
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