Answer:
We use z-test for this hypothesis.
![z_(stat) = 2.23](https://img.qammunity.org/2020/formulas/mathematics/college/nrauyw1jbw4ba658vm3gr32klqfail79po.png)
Explanation:
We are given the following in the question:
Population mean, μ = 4.88
Sample mean,
= 5.91
Sample size, n = 48
Alpha, α = 0.05
Population standard deviation, σ = 3.2
First, we design the null and the alternate hypothesis
![H_(0): \mu = 4.88\\H_A: \mu > 4.88](https://img.qammunity.org/2020/formulas/mathematics/college/lkgzqqqipftlgv96bobhnsz4qpwjamqg4w.png)
The null hypothesis states that the mean score of successful managers on a psychological test is 4.88 and the alternate hypothesis says that the mean score of successful managers on a psychological test is greater than 4.88.
We use One-tailed z test to perform this hypothesis.
Formula:
![z_(stat) = \displaystyle\frac{\bar{x} - \mu}{(\sigma)/(√(n)) }](https://img.qammunity.org/2020/formulas/mathematics/college/2874qm4r8wzlnyepitoddzym0xmflvhckh.png)
Putting all the values, we have
![z_(stat) = \displaystyle(5.91 - 4.88)/((3.2)/(√(48)) ) = 2.23](https://img.qammunity.org/2020/formulas/mathematics/college/6tdpuh8xzzcuhzmgxmu26m4j8cskep0xrm.png)