SOLUTION: I need some much needed assistance with this. Can someone help?.... A researcher claims that the average age of people who buy lottery tickets is 61. A sample of 30 is selected

Algebra ->  Probability-and-statistics -> SOLUTION: I need some much needed assistance with this. Can someone help?.... A researcher claims that the average age of people who buy lottery tickets is 61. A sample of 30 is selected       Log On


   

Question 624732: I need some much needed assistance with this. Can someone help?....
A researcher claims that the average age of people who buy lottery tickets is 61. A sample of 30 is selected and their ages are recorded as shown below. The standard deviation is 8. At a
= 0.01 is there enough evidence to reject the researcher’s claim? Show all work.
49
63
66
52
25
80
72
56
33
56

51
46
70
74
70
61
65
71
28
74

79
76
35
49
62
68
54
67
69
45
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

Note: *Note: z+=blue+%28x+-+mu%29%2Fblue%28sigma%2Fsqrt%28n%29%29

X  = 62.5

 z = %2862.5-61%29%2F%288%2Fsqrt%2830%29%29 = 1 .0267 

At a = 0.01 (z = 2.576) is there enough evidence to reject the researcher’s claim

NO, 1.0267 < 2.576



________________________________________________________________________

	a	a/2	crtical regions	

80%	0.2	10%	z <-1.28155     z >+1.28155

90%	0.1	5%	z <-1.645	          z >+1.645

92%	0.8	4%	z <-1.751	          z >+1.751

95%	0.05	2.50%	z <-1.96	          z >+1.96

98%	0.02	1%	z <-2.326	          z >+2.326

99%	0.01	0.50%	z<-2.576	          z >+2.576