Answer Happy

Need answers to part a and b. Please note that both parts a and
b correspond to one question.
(a) The following table shows the ages (in years) of a random sample of 20 patients in a hospital. 21 22 25 19-R 37 25 40 28 45 31 47 33 48 34 50 36 51+R 37 39 44 Suppose a 6-class grouped frequency distribution is to be constructed for the above data using the smallest data value as the lower class limit for the first class. (1) Find the class width. (ii) Find the upper class limit of the 2nd class. (iii) Find the lower class boundary of the 3rd class. (iv) Find the percentile rank for the patient who is 33 years old. (v) Find the 45th percentile of the data set. The following grouped frequency distribution summarized the test scores of a sample of students. (4 marks) (2 marks) (2 marks) (2 marks) (2 marks) (b) Score 40 - 46 47-53 54 - 60 61-6 68 - 74 75-81 Frequency 7 4+R 10 5 12-R 4 Find the following using the grouped frequency distribution above. (i) Sample mean (ii) Sample variance (3 marks) (5 marks)