1. IUBAT–INTERNATIONAL UNIVERSITY OF BUSINESS AGRICULTURE AND TECHNOLOGY
Special examination
STA 240 Set: W
Full marks: 35 Time: 2 hours
1. Let code the following values as Dhaka (1), Khulna (2), Chittagong (3), Others (4):
134213421342134213432322134231432314314
a) Construct a frequency table for the given data. (2)
b) Construct relative frequency column in that table. (1)
c) Construct percentage column in that table. (1)
2. Which measure of dispersion is the best? Why? (3)
3. Find the mean and mode for the series 1, 2, 3 ……… 900. (2)
4. Find the two numbers whose AM=10 and GM=8. (3)
5. Why we study coefficient of variation (CV)? (1)
6. Find the two numbers whose AM=7 and SD=1. (2)
7. Find the MD and SD of the numbers 0, 2,3,4,5. (4)
8. What is the sample space for choosing 1 letter at random from 5 vowels? (1)
9. Two dice are rolled; find the probability that the sum is equal to 8. (2)
10. Write down the applications of Poisson distribution. (2)
11. Explain the concept of stratified sampling with an example. (2)
12. Let X=fertilizer, Y=production of rice.
X: 1 2 3
Y: 4 6 8
a) Find the correlation coefficient, r. (2)
b) Fit a regression line between X and Y. (3)
13. Define the following terms with example: (4)
a) Null hypothesis (b) critical region (c) type I error (d) two sided test.