BITM 3rd Semester
Business Statistics Board Question Paper 2022

TRIBHUVAN UNIVERSITY
FACULTY OF MANAGEMENT
Office of the Dean
January 2022
Full Marks:36 Pass Marks:18 Time:2 hrs
BBA / BIM / BITM /
Third Semester /
STT 211:
Business Statistics

Candidates are required to give their answers in their own words as for as practicable.
The figures in the margin indicate full marks

Long Answer Questions
Section "A"

Brief Answer Questions:

[4×2 = 8]
1.

Consider the following set of sample data:

781211438811010762122130957813989125

Calculate the lower and upper quartiles.

2.

If the coefficient of skewness is 0.5, first quartile is 8 and third quartile is 16, find the median of the distribution.

3.

A bag contains 20 balls numbered from 1 to 20. A ball is selected at random without replacement, what is the probability of (a) multiple of 3 or 7 (b) multiple of 3 or 4?

4.

A random variable x has the following probability distribution.

X01234
P(x)0.220.180.350.150.10

Compute the expected value and variance.

Section "B"

Short Answer Questions:

[4×3=12]
5.

Compute the five number summaries from the following data and comment on the shape of the distribution:

71125231934293191530

6.

Find the mean and standard deviation from the following data related to age distribution of a class.

Age (yrs)151617181920
No of students57121574

7.

The mean height and variance of height of 500 students were found to be 165 cm and 25 cm² respectively. Find the range of height of middle 80% of the students.

8.

A sample of heights of 6400 Indian has a mean of 67.85 inches with a standard deviation of 2.56 inches, while sample of heights of 1600 British has a mean of 68.55 inches with a standard deviation of 2.52 inches. Do the data indicate that British are on the average taller than Indians at 5% level of significance?

Section "C"

Comprehensive Answer Questions:

[2×8=16]
9.

The following table shows the monthly expenditure of people living in village A and village B of a country.

Expenditure (000 Rs)51015202530
No. of families in village A4145120104
No. of families in village B8184018129

Which village people have uniform expenditure on the basis of coefficient of variation?

10.

A random sample of 12 records revealed the following information concerning the number of machines serviced and the time (in minutes) to complete the routine service call:

No. of machines1189107684105512
Service time (minutes)11560809055657033955040110

a) Calculate coefficient of correlation and interpret.
b) Estimate the regression equation. If there are six machines, how many minutes should expect a routine service call to require?