Question

1A) An experiment was 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 litter-mates. The rations were assigned at random to the two animals within each pair. The gains (in pounds) after 45 days are shown in the following table. Assuming weight gain is normal, find the 95% confidence interval estimate for the mean of the differences μ_d, where d = ration A - ration B. (Give your answers correct to two decimal places.)

Litter	1	2	3	4	5	6	7	8
Ration A	65	50	47	65	47	53	61	46
Ration B	60	40	37	57	39	52	57	38

Lower Limit -

Upper Limit -

1B) Find the 95% confidence interval for the difference between two means based on this information about two samples. Assume independent samples from normal populations. (Use conservative degrees of freedom.) (Give your answers correct to two decimal places.)

Sample	Number	Mean	Std. Dev.
1	18	37	31
2	14	27	32

Lower Limit -

Upper Limit -

Answer 1

1)

from above:

Lower Limit -4.12

Upper Limit -9.38

1b)

Lower Limit --14.30

Upper Limit - 34.30