Question

25 graduating seniors from stellar high school are randomly selected. a mean gpa of 3.42 is calculated with a margin of error ±0.38 for a 95% confidence interval. what is the interval estimate of the population mean? a 2.87 < μ < 3.63 b 3.04 < μ < 3.80 c 3.04 > μ > 3.80 d 3.06 > μ > 3.78 e 3.06 < μ < 3.78

Explanation:

Step1: Calculate lower - bound

Subtract margin of error from sample mean.
$3.42 - 0.38=3.04$

Step2: Calculate upper - bound

Add margin of error to sample mean.
$3.42 + 0.38 = 3.80$

Answer:

B. $3.04<\mu<3.80$