Answer: 95% confidence interval = 20,000 ± 2.12![\times](https://tex.z-dn.net/?f=%5Ctimes)
![\frac{1500}{\sqrt{17} }](https://tex.z-dn.net/?f=%5Cfrac%7B1500%7D%7B%5Csqrt%7B17%7D%20%7D)
( 19228.736 , 20771.263 ) OR ( 19229 , 20771 )
Step-by-step explanation:
Given :
Sample size(n) = 17
Sample mean = 20000
Sample standard deviation = 1,500
5% confidence
∴
= 0.025
Degree of freedom (
) = n-1 = 16
∵ Critical value at ( 0.025 , 16 ) = 2.12
∴ 95% confidence interval = mean ± ![Z_{c}](https://tex.z-dn.net/?f=Z_%7Bc%7D)
![\times](https://tex.z-dn.net/?f=%5Ctimes)
![\frac{\sigma}{\sqrt{n} }](https://tex.z-dn.net/?f=%5Cfrac%7B%5Csigma%7D%7B%5Csqrt%7Bn%7D%20%7D)
Critical value at 95% confidence interval = 20,000 ± 2.12![\times](https://tex.z-dn.net/?f=%5Ctimes)
![\frac{1500}{\sqrt{17} }](https://tex.z-dn.net/?f=%5Cfrac%7B1500%7D%7B%5Csqrt%7B17%7D%20%7D)
( 19228.736 , 20771.263 ) OR ( 19229 , 20771 )