Question

It is believed that 62% of Americans think that foreign made cars are higher quality than American made cars. After a recent advertising campaign sponsored by American auto makers, a research company wants to determine if that percentage has decreased. Which inference technique would we use? a) A hypothesis test for means. b) A confidence interval for proportions. c) A confidence interval for means. d) A hypothesis test for proportions. Construct a 95% confidence interval for the difference between the two independent population means. Brand X n = 35 S = 1.4 Brandy = 40 x = 15. 1 5 +0.8 a) (3.8.4.8) b) (3.6.5.0) c) (3.5.5.1) d) (-4.7.-3.9) * = 19.4 In order to test whether raw garlic is effective in lowering LDL cholesterol, a group of 49 subjects were treated and the change in their cholesterol levels before and after treatment were analyzed. A hypothesis test was performed with, Ho: He=0 Raw garlic is not effective in lowering mean LDL cholesterol level. H K O Raw garlic is effective in lowering mean LDL cholesterol level. What conclusion would be made if the P-value was very low? a) There is no evidence that raw garlic is effective in lowering mean LDL cholesterol level. b) There is evidence that raw garlic is not effective in lowering mean LDL cholesterol level. c) There is evidence that raw garlic is effective in lowering mean LDL cholesterol level. d) No conclusion can be made because the sample was too small