SOLUTION: I really need help with this question' If we wish to have a 98% confidence interval, what would be the value of α /2? Show how you arrived at this answer

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Question 406179: I really need help with this question'
If we wish to have a 98% confidence interval, what would be the value of α /2? Show how you arrived at this answer
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

the 98% confidence interval is two-tailed, .01 on the right and left:

	α	α/2	crtical regions	

98%	2%	1%	z <-2.33	z >+2.33   NORMSINV(0.01)= 2.3263

Note graph: between the two blue lines represents 98% of the distribution





If a population has a standard deviation σ of 25 units, what is the standard error of the mean 

if samples of size 16 are selected? Samples of size 36? Samples of size 100?

σ[M] = [25/sqrt(16)] 		

σ[M] = [25/sqrt(36)]

σ[M] = [25/sqrt(100)]