Business Statistics Old Question Paper Year 2018 | Tribhuvan University | Program BBA
Brief Answer Questions: [4×2=8]
- 1) What is sampling? List down the various random sampling techniques.
- 2) One hundred and twenty Students appeared for a English class test and following are the marks distribution.
|No. of students||10||25||40||30||15|
Find the modal marks of the students.
- 3) A bag contains 3 red, 2 black and 5 white balls. If two balls are drawn at random, what is the probability of getting () both red balls (ii) both white balls.
- 4) A random sample of 100 patients suffering from a certain disease was given a serum treatment. It was observed that 80% were relieved of the disease. Find 99% confidence limits for the percentage of patients cured.
Short Answer Questions: [4×3=12]
- 5) If the average value of Poisson distribution is 2. Find the value of
(i)P(x = 0) (ii) (x<=1) (ii) P(x >= 2)
- 6) Lives of two models of refrigerators in a recent survey are shown below
|Model A||Model B|
|Average life in years||5||6|
Which model of refrigerators has greater uniformity in life?
- 7) Following are the income distributions of the 600 employees.
|Income ‘000’ Rs:||0-50||50-100||100-150||150-200||200-250||250-300|
|No. of employees||40||160||200||100||70||30|
Find the lowest income of richest 15% of employees.
- 8) The following table gives the information of average number of articles produced by Machine A and Machine B respectively with their standard deviations. Test whether the both machines equally efficient on the basis of 50 days of production at 5% level of significance.
|Machine A||Machine B|
|Average numbers of articles||200||210|
Comprehensive Answer Questions:
- 9) The following table gives aptitude test scores and productivity indices of 8 randomly selected workers. Find the correlation coefficient aptitude score and productivity index.
Estimate the productivity index of a worker whose test score is 66.
- From the following distribution, find skewness and kurtosis. Also comment on the results.
|Marks||No. of students|