We can use the formula:
( X̄ - z*(σ/√n), X̄ + z*(σ/√n) )
where:
X̄ = sample mean = 3.37
z = z-score for desired confidence level = 1.96 (from a standard normal distribution)
σ = population standard deviation = 0.28
n = sample size = 120
Plugging in the values, we get:
( 3.37 - 1.96*(0.28/√120), 3.37 + 1.96*(0.28/√120) )
Simplifying, we get:
( 3.28, 3.46 )
Therefore, we are 95% confident that the true mean undergraduate GPA for students admitted to the top graduate business schools is between 3.28 and 3.46.
The undergraduate grade point (GPA) for students admitted to the top graduate business shools was 3.37 assume this estimate was based on a sample of 120 students admited to the top schools, using past year data the population standard deviation can be assumed known with standard deviation = .28 what is the 95% confidence interval estimate of the mean undergraduate GPA for students admited to the top graduate business school?
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