mean noise level in 171 randomly selected ward area 58.0 decibelsthe population standard deviation 4.8. Find the 90% confidence interval of the true mean.

Question

i need help with this question and many others and im hoping you can help me thanks

Answer 1

1.645* 4.8/sqrt(171) = 0.60382221154732...

 

The confidence interval is the sample mean, plus and minus the value calculated above.

 

The confidence interval is:

 

  (58 - 0.6038222115473, 58 + 0.6038222115473)=

 

  (57.3961777884527, 58.6038222115473)

 

The population mean is inside that interval with 90% certainty