Reference no: EM13615526

1.Using the Z table to find the critical value(s) for each (P 407) <br/>a) a = 0.04, left-tailed test <br/>b) a = 0.05, two-tailed test <br/>c) a = 0.005, right-tailed test <br/> <br/>2.Write down the hypothesis for each of the following: (P 400, 401, 410) <br/>a) An additive is claimed to improve automotive battery life (mean: 3 years) <br/>b) Robot can reduce car assembly manufacturing defect to less than 20 C/100 <br/>c) Music is known to affect the test score (mean: 80) but do not know better or worse <br/>e) Good job opportunity affect the college student age (ave: 25 yrs) <br/> <br/>3. a) Walking (µ = 5 000 steps/day and s = 600 steps/day) is shown to improve health. A group of 40 <br/> health-conscious employees take average of 5430 steps/day. At a = 0.05 can it be concluded <br/> that they walked more than the mean? (P 411) <br/> b) US Senators (µ = 60 yrs and population s = 6.5 yrs), while state senators may be different. <br/> A random sample of 40 from various states has an average of 55 years. <br/> At a = 0.05 is there sufficient evidence that state senators are younger on average? <br/> c) State whether the null hypothesis should be rejected on the basis of given P value (P 417) <br/> I) P value = 0.258 a = 0.05, one-tailed test II) P value = 0.0684 a = 0.10, two-tailed test <br/> d) Home prices in two cities were compared to see if there is a difference at a = 0.01. (P 474) <br/> Scott X1 bar = $93,430, s1= $5602, n1 = 35; <br/> Ligonier X2 bar = $98,043, s2 = $4731, n2 = 40 <br/> <br/> Is there enough evidence to reject the claim that the average price is the same? <br/> <br/>4.PGA Golf Scores At a recent PGA tournament (the Honda Classic at Palm Beach Gardens, Florida) the following scores were posted for eight randomly selected golfers for two consecutive days. <br/>(a) At a = 0.05, is there evidence of a difference in mean scores for the two days? <br/>(b) Find the 95% confidence interval of the difference in the means. <br/>Golfer1 2 3 4 5 6 7 8 <br/>Thursday67 65 68 68 68 70 69 70 <br/>Friday 68 70 69 71 72 69 70 70 <br/> <br/>5. Prices of Low-Calorie Foods The average price of a sample of 12 bottles of diet salad dressing taken from different stores is $1.43. The standard deviation is $0.09. The average price of a sample of 16 low-calorie frozen desserts is $1.03. The standard deviation is $0.10. <br/>(a) At a = 0.01, is there a significant difference in price? <br/>(b) Find the 99% confidence interval of the difference in the means. <br/>