Exhibit 8-2
The manager of a grocery store has taken a random sample of 100 customers. The average length of time it took these 100 customers to check out was 3.0 minutes. It is known that the standard deviation of the checkout time is one minute.
-Refer to Exhibit 8-2. With a .95 probability, the sample mean will provide a margin of error of
A)0.95
B)0.10
C).196
D)1.96

Question

Quizplus · Accepted Answer

The margin of error for a sample mean with known standard deviation is calculated using the formula: Margin of Error = Z * (σ/√n). For a 95% confidence level, Z is approximately 1.96. Given σ = 1 and n = 100, the margin of error is 1.96 * (1/√100) = 0.196.

Exhibit 8-2 The Manager of a Grocery Store Has Taken a Random