Question 438330
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Hi
A poll was taken of 500 College graduates. 
The college graduates sampled were asked whether Americans feel satisfied with their lives; 
350 responded “very satisfied” Use this date to obtain a 97% confidence
 interval for the corresponding population proporation, p. 
p-hat = 350/500 = .7
97% confidence then z = 2.1701
ME =  2.1701*sqrt[0.7*0.3/500] = 0.04447
97%CI: 0.7-0.04447 < p < 0.7+0.04447
97%CI: 0.6555< p < 0.7448

Summary of other critical regions
	a	a/2	crtical regions	
90%	0.1	5%	z <-1.645	z >+1.645
95%	0.05	2.50%	z <-1.96	z >+1.96
98%	0.02	1%	z <-2.33	z >+2.33
99%	0.01	0.50%	z<-2.575	z >+2.575