Answer:
a)
i) Mean = 72
ii) Median = 72
iii) Mode = 72
b)
69, 70, 71, 72, 72, 72, 73, 74, 75
Explanation:
a. To find mean, median and mode
It is given that all the 9 students get 72 marks.
Therefore the data set be,
72, 72, 72, 72, 72, 72, 72, 72 72
i) mean = (sum of data)/(total number of data)
= (9 * 72)/9 = 9
ii) Median - Central data in the data set when arranging ascending or descending order
72, 72, 72, 72, 72, 72, 72, 72 72
Median = 72
iii) Mode - Most repeating data in the data set
Here mode = 72
b). To find a data set
69, 70, 71, 72, 72, 72, 73, 74, 75
Here Mean, mode and median are all 72