# Pondicherry University 2009 B.C.A Computer Application , PROBABILITY AND STATISTICS - Question Paper

Monday, 28 January 2013 12:25Web

B.C.A DEGREE EXAMINATION, MAY 2009

Second semester

Computer applications

Allied- PROBABILITY AND STATISTICS

TIME: three hours Max mark: 100

**PART-A**(10*2=20 MARKS)

ans ALL QUESTINS

1. Define primary and secondary data.

2. Define Ogives curve and methods of constructing Ogives.

3. Calculate mean from the flg data.

R.No 1 2 3 4 5 6 7 8 9 10

Marks 40 55 78 58 60 73 35 43 48 50

4. What do you mean by coefficient of dispersion?

5. Define Kurtosis.

6. Write any 2 properties of regression coefficient.

7. Write the sample space for the Random.

8. Define mathematical expectation.

9. What do you mean by critical value?

10. What is contingency table?

**PART-B**(5*6=30 MARKS)

ans ANY 5 ques..

11. Explain the parts of tabulation.

12. Calculate the mode from the flg series.

size

4

5

6

7

8

9

10

11

12

14

15

16

17

18

19

frequency

40

48

52

57

60

63

57

55

50

41

57

63

52

48

40

13. Find the coefficient of variance (C.

**V)**of a frequency distribution provided that its mean is 120, mode is and Karl Pearson’s coefficient of skew ness is -0.3.

14. the monthly income of 10 families in rupees in a certain locality are provided below:

Family A B C D E F G H I J

Income (Rs.) 85 70 10 75 500 8 42 250 40 36

compute the geometric mean and harmonic mean.

15. If twice dice are thrown. What is the probability that the sum is

**(**great than eight and

**a)****(**neither seven or 11?

**b)**16. Fit a Poisson distribution to the subsequent data and compute the expected frequencies.

X: 0 1 2 3 4 5 6 7 8

ƒ: 71 112 117 57 27 11 3 1 1

17. Write a short note on the chi square test of goodness of fit of a random of fit of random sample to a hypothecal distribution.

18. The heights of 10 males of a provided locality are obtained to be 70, 67,62,68,61,70,64,

**6**Is it reasonable to believe that the avg. height is greater than 64 inches? Test at 5% significal level, assuming that for nine degrees of freedom, P. (t>1.

**6.****8**=0.05.

**3)****PART-C**(5*10= 50 MARKS)

ans ALL ques..

19. Represented by a percentage bar diagram the flg data on investment for the 1st and 2nd five-year plans:

Investment in the public sector.

Items 1st 5 year second 5 year

Plan plan

Agriculture 357 768

Irrigation 492 990

Industry 261 909

Transport 654 1485

Social studies 305 945

Miscellaneous 90 300

Or

**20.**Prepare a histogram and a frequency polygon form the subsequent data:

Class ƒ

0-6 4

6-12 8

12-18 15

18-24 2024-30 1230-36 6

**2**compute the median, three rd decile and 20th percentile the flg data:

**1.**x: 0-5 5-10 10-15 15-20 20-25

ƒ: 7 18 25 30 20

or

**2**compute the arithmetic mean, median and mode form the flg data.

**2.**Age at last birthday number

15-19 4

20-24 20

25-29 38

30-34 24

35-39 10

40-44 9

**2**from the subsequent data compute coefficient of rand correlation ranging from X and Y. Also compute Karl Pearson’s coefficient of correlation

**3.**x: 36 56 20 65 42 33 44 50 15 60

?: 50 35 70 25 58 75 60 45 80 38

Or

**2**compute the 2 regression formula of X on Y and Y on X from the data provided below, taking derivations from true means of X and Y.

**4.**Price : 10 12 13 12 16 15

Amount demanded: 40 38 43 45 37 43

Estimate the likely demand when the price is Rs.20.

**2**State and prove Baye’s theorem.

**5.**Or

**2**7 coins are tossed and no of heads noted the experiments is repeated 128 times and the subsequent distribution is found

**6.**No. of heads: 0 1 2 3 4 5 6 7

Frequencies: 7 6 19 35 30 23 7 1

Fit a binomial distribution to the above data when the coin is unbiased.

27. if ?²1, and ?²2 are 2 independent ?² variables with n1 and n2 degrees of freedom (d.

**f)**respectively, then

?²1/ ?²2 is a ß2 (n1/2, n2/

**2)**variate.

Or

28. Two random samples gave the flg outcomes.

Sample size sample mean sum of squares Of deviation

From the mean

1 10 15 90

2 12 14 108

Test whether the samples come form the identical normal population at 5% level of significance.

(Given = F0.05 (9,

**1**= 2.90, F0.05 (11,

**1)****9)**= 3.10(approx.) and t0.05

**(**=2.086, t0.05

**20)****(**=2.07).

**2****2)**____________

Earning: Approval pending. |