Answer: The 95% confidence interval would be (4.57,4.63).
Explanation:
Since we have given that
N = 1000 typical loans
Mean = 4.6 errors
Standard deviation = 0.5 errors
At 95% confidence, z = 1.96
So, 95% confidence interval on the true mean error rate is given by
Hence, the 95% confidence interval would be (4.57,4.63).