Business Statistics
Test
Max Marks: 20
Ques 1. The ages (in years) of a sample of 25 teachers are as follows:
47
40
34
38
30
a.
b.
c.
d.
21
30
24
35
45
37
32
24
28
31
53
34
35
43
41
28
26
45
45
56
Draw a frequency histogram of this data which contains four classes.
Draw a stem-and-leaf display and an ogive for this data.
Describe your findings.
Make and interpret box plot for this data and identify the outliers if any.
10 Marks
Ques 2. Suppose that the amount of time teenagers spend playing computer games per week is
normally distributed with a standard deviation of 1.5 hours. A sample of 100 teenagers is
selected at random, and the sample mean computed as 6.5 hours. Determine the 99% confidence
interval estimate of the population mean and interpret your results.
3 Marks
Ques 3. Suppose that past history shows that 5% of college students are sports fans. A sample of
10 students is to be selected. Using Binomial distribution, find the probability that at least 3
student is a sports fan.
2 Marks
Ques 4. A random sample of 12 second-year University students enrolled in a Business Statistics
course was drawn. At the course’s completion, each student was asked how many hours he or
she spent doing homework in statistics. The data are listed below. The instructor has
recommended that students devote 30 hours per week for the same. Test to determine whether
there is evidence that the average student spent the recommended amount of time. Test at 5%
level of significance.
31
40
26
30
36
38
29
40
38
30
35
38
5 Marks