Answer: 385
Given: error: 6 months, standard deviation = 5 years is 60 months
Step 1: find the minimal sample size ‘n’ for 95% confidence interval
1-0.95= 0.05
0.05/2= 0.025
Step 2:
1-0.025= 0.975
View attachment for more steps
Given: error: 6 months, standard deviation = 5 years is 60 months
Step 1: find the minimal sample size ‘n’ for 95% confidence interval
1-0.95= 0.05
0.05/2= 0.025
Step 2:
1-0.025= 0.975
View attachment for more steps