10A / 297 CLASS: B.Com. St. JOSEPH’S COLLEGE (AUTONOMOUS) TIRUCHIRAPPALLI – 620 002 SEMESTER EXAMINATIONS – APRIL 2010 TIME: 3 Hrs. MAXIMUM MARKS: 100 SEM SET PAPER CODE TITLE OF THE PAPER IV 2008 08UCO430404 ALLIED OPT: ELEMENTS OF STATISTICS SECTION – A Answer all the questions: 20 x 1 = 20 Choose the correct answer: 1. 2. The median of 8, 10, 5, 9, 12, 11 is a) 9 b) 10 c) 9.5 d) 10.5 b) Mean Median S.D Mean Mode Median The Karl Pearson’s coefficient o skewness is a) c) 3. c) 5. d) The probability of getting 6 in the first die a) 4. Mean Mode S.D 3(Mean Mode) S.D 1 36 5 36 b) d) 2 36 1 6 The index number which is from arithmetic mean of Laspeyro’s and Paasche’s method is a) Fisher’s Ideal Method b) Bowley Dorfish method c) Klalsch’s method d) Kethey’s method The formula is used when figures to be interpolated is in the middle of the series a) Newton’s difference formula b) Newton’s forward formula c) Newton’s backward formula d) None of these State True or False: 6. Mean – Median = 3(Mean – Mode) 7. Coefficient of Mean deviation is Mean deviation . Median 8. When thins are arranged in a circle, we find two ends in each arrangement. 9. In free – hand method, the sum of the squares of the vertical deviations from the trend should be as large as possible. 10. Newton’s divided difference method is used when the value of independent variable x advances by unequal intervals. Fill in the blanks: 11. The data are classified according to some characteristic is known as ______ classification. 12. The value of the coefficient of correlation lie between ______ and ______. 13. If the events are not mutually exclusive then P (A B) = ______. 14. The general tendency of the time series data to increase or decrease or stagnets during a long period of time is called ______. 15. Newton’s formula for interpolating the value of y for a given value of x is ______. Answer in one or two sentences: 16. Define secondary data. 17. Find the 40, 43. 18. Define equally likely events. 19. Say anyone essential requirement of time series. 20. What are the two major methods of Interpolation. range of weights of 7 students from 27, 40, 35, 36, SECTION – B Answer all the questions: 21. a. 5 x 4 = 20 What are the rules of classification. Explain it. OR b. Calculate the median from the following table. Marks Frequency 10-25 25-40 40-55 55-70 70-85 85-100 6 20 44 26 3 1 38, 22. a. For a group of 50 male workers, the mean and the standard deviation of their waves are Rs.63 and Rs.9 respectively. For a group of 40 female workers these are Rs.54 and Rs.6 respectively. Find the standard deviation for the combined group of 90 workers. OR b. 23. a. Find Karl Pearson’s coefficient of correlation from the following data. Wages 100 101 102 102 100 99 97 98 96 95 Cost of living 98 99 99 97 95 92 95 94 90 91 A bag contains 7 red balls and 5 white balls. 4 balls are drawn at random. What is the probability that (i) all of them are red. (ii) two of them are red and two white? OR b. The odds in favour of a certain event are 2 to 5 and the odds against another event independent of the former are 5 to 6. Find the chance that one atleast of the events will happen. 24. a. Explain briefly about the two types of the time series models. OR b. An enquiry into the budgets of middle class families in a certain city gave the following information. Expenses Food 35% Fuel 10% Cloth 20% Rent 15% Miscellaneous 20% Prices (Rs) (1995) 150 25 75 30 40 Prices (Rs) (1996) 145 23 65 30 45 What is the cost of living index number of 1996 as compared with that of 1995? 25. a. Interpolate the figure of population for the year 1996 from the following data : Year Population of a town 1960 1970 1980 1990 25,494 29,003 32,528 36,070 OR b. Use Lagrange’s interpolation formula to find y when x = 0, given the following table. x -1 -2 2 4 y -1 -9 11 69 SECTION – C Answer any FOUR questions: 26. 27. The frequency distribution of weight in grams of mangoes of a given variety is given below. Calculate the arithmetic mean, median and mode. 29. Weight (in gms) No of mangoes Weight (in gms) No. of mangoes 410 – 419 14 450 – 459 45 420 – 429 20 460 – 469 18 430 – 439 42 470 – 479 7 444 – 449 54 Calculate Karl Pearson’s coefficient of skewness for the following data 25 28. 4 x 15 = 60 15 23 40 27 25 23 25 20 Two dice are thrown. Find the probability that a. the sum of the numbers shown by the dice is exactly 6. b. the total of the numbers on the dice is greater than 8. c. the total of the numbers on the dice is greater than 8. d. the total of the numbers on the dice is 13. e. the first die shoes 6. The following table gives the sterling assets of the R. B. I in crores of rupees. a. Represent the data graphically b. Fit a straight line trend. c. Show the trend on the graph. Year 1986-87 1987-88 1988-89 1989-90 1990-91 1991-92 Assets 83 92 71 90 Also estimate the figures for 1996-97. 30. From the following table, estimate the value of y when x = 65 x 31 41 51 61 71 y 46 66 81 93 101 ************** 169 191