Answer: 1.300228
Step-by-step explanation:
The t-score we use for the confidence interval is two-tailed , i.e. the t-score should be used to find a () is given by :-
, where n is the sample size.
Given : Level of confidence:
Significance level :
Sample size : n= 47
Then, degree of freedom :
Now by using standard normal t-distribution table,
Hence, the t-score should be used to find a 80% confidence interval estimate for the population mean = 1.300228