1. A small accounting firm pays each of its five clerks Rs 25000, two junior accountants Rs 60000, and the firm’s owner Rs 255000. What is the mean salary paid at this firm? How many of the employees earn less than the mean? What is the median salary?
2. Nonstandard dice can produce interesting distributions of outcomes. You have two balanced, six-sided dice. One is a standard dice, with faces having 1,2,3,4,5 and 6 spots. The other die has three faces with 0 spots and three faces with 6 spots. Find the probability distribution for the total number of spots Y on the up-faces when you roll these two dice.
3. What is a chi-square test? How do you find the degrees of freedom in a chi-square distribution? Discuss chi-square test as a test for goodness of fit and as a test of independence.
4. A study of iron deficiency among infants compared samples of infants following different feeding regimens. One group contained breast-fed infants, while the children in other group were fed a standard baby formula without any iron supplements. Here are summary results on blood hemoglobin levels at 12 months of age.
| Group | n | Mean | s |
| Breast-fed | 23 | 13.3 | 1.7 |
| Formula | 19 | 12.4 | 1.8 |
a. Is there significant evidence that the mean hemoglobin level is higher among breast- fed babies? State null hypothesis and alternate hypothesis and conduct a t-test.
b. Give a 95% confidence interval for the mean difference in hemoglobin level between the two populations of infants.
5. What do you mean by a seasonal index? Explain ratio to link relatives method of measuring seasonal variations.