Reference no: EM13602236

Question 1

Based on a survey of 1,000 adults by Greenfield Online and resported in a May 2009 USA Today Snapshot, adults 24 years of age and under spend a weekly average of $35 on fast food. If 200 of the adults surveyed were in the age catetory of 24 and under and they provided a standard deviation of $14.50, construct a 95% confidence interval for the weekly average expenditure on fast food for adults 24 years of age and under. Assume fast food weekly expenditures are normally distributed.

Question 2

An experiment ws designed to estimate the mean difference in weight gain for pigs fed ration A as compared with those fed ration B. Eight pairs of pigs were used. The pigs within each pair were littermates. The rations were assigned at random to the two animals within each pair. The gains (in pounds) after 45 days are shown below:

                                                                                                                                                                                                                                                                                                                                                                                

RationA	RationB
65	58
37	39
40	31
47	45
49	47
65	55
53	59
59	51

Assuming weight gain is normal, find the 95% confidence interval estimate for the mean of the differences ?_d where d= ration A - ration B.