A random sample of 35 business students required an average of 50.7 minutes to complete a statistics exam. Assume that the population standard deviation to complete the exam was 10.4 minutes. The 95% confidence interval around this sample mean is ________.
A)(48.9, 52.5)
B)(47.3, 54.1)
C)(49.8, 51.6)
D)(45.4, 56.0)

Question

Quizplus · Accepted Answer

The 95% confidence interval is calculated using the formula: mean ± (Z * (σ/√n)). Here, Z is 1.96 for 95% confidence, σ is 10.4, and n is 35. This gives the interval (47.3, 54.1).

A Random Sample of 35 Business Students Required an Average