In an inter-school competition, there are a total of 14 participants. Each participant answered 20 multiple
choice questions. Below are the numbers of correct answers obtained by the participants:
16, 11, 20, 19, 18, 17, 15, 16, 17, 19, 20, 17, 13, 13
(a) Find the mean, 90
th
percentile, interquartile range, and standard deviation of the number of correct
answers obtained by a participant.
(b) Each participant has a basic score of 100 points. For each correct answer, 20 points would be given; for
each wrong answer, 10 points would be deducted. Use X to represent the number of correct answers
and Y to represent the final points of the participant, express Y as a linear function of X.
(c) Find the following summary statistics of the final points a participant gets in this competition:
Mean, standard deviation, interquartile range, maximum.
(d) Write a simple summary report (in around 30 – 50 words) about the final points of a participant gets in
this inter-school competition. (The summary report needs to include all summary statistics found in part
(c)).