A sample of 400 employees from a particular software company had a mean monthly income of $\$ 7288$ with a standard deviation of $\$ 2763$. Find the $95 \%$ confidence interval. Round your answer to the nearest dollar.
A) $\$ 6984

Question

A sample of 400 employees from a particular software company had a mean monthly income of $\$ 7288$ with a standard deviation of $\$ 2763$. Find the $95 \%$ confidence interval. Round your answer to the nearest dollar.
A) $\$ 6984 < \mu < \$ 7592$
B) $\$ 7150 < \mu < \$ 7426$
C) $\$ 7274 < \mu < \$ 7302$
D) $\$ 7012 < \mu < \$ 7564$

Quizplus · Accepted Answer

The 95% confidence interval is calculated using the formula: mean ± (Z * (standard deviation/√n)). Here, Z is approximately 1.96 for 95% confidence. Calculating gives: 7288 ± (1.96 * (2763/√400)) = 7288 ± 276, which results in the interval \$7012 to \$7564.

A Sample of 400 Employees from a Particular Software Company $7288\$ 7288$7288

A Sample of 400 Employees from a Particular Software Company $\$ 7288$