Respuesta :
Answer:
The test statistics is [tex]z = -1[/tex]
Step-by-step explanation:
From the question we are told that
The sample size is n = 100
The null hypothesis is [tex]H_o : \mu = \$30000[/tex]
The alternative hypothesis is [tex]H_a : \mu < \$ 30000[/tex]
The sample mean is [tex]\= x = \$29,750[/tex]
The standard deviation is [tex]\sigma = \$2,500[/tex]
The level of significance is [tex]\alpha =0.05[/tex]
Generally the test statistics is mathematically represented as
[tex]z = \frac{\= x - \mu }{ \frac{ \sigma}{ \sqrt{n} } }[/tex]
=> [tex]z = \frac{29750 - 30000 }{ \frac{ 2500}{ \sqrt{100} } }[/tex]
=> [tex]z = -1[/tex]
From the desired test, we have that:
a)
- The null hypothesis is: [tex]H_0: \mu \geq 30000[/tex]
- The alternative hypothesis is: [tex]H_1: \mu < 30000[/tex]
b) The t-statistic is t = -1.
Item a:
At the null hypothesis, we test if the average starting salary for clerical employees in the state is not less than $30,000, that is:
[tex]H_0: \mu \geq 30000[/tex]
At the alternative hypothesis, it is tested if the salary is less than $30,000, that is:
[tex]H_1: \mu < 30000[/tex]
Item b:
We have the standard deviation for the sample, thus, the t-distribution is used. The test statistic is given by:
[tex]t = \frac{\overline{x} - \mu}{\frac{s}{\sqrt{n}}}[/tex]
The parameters are:
- [tex]\overline{x}[/tex] is the sample mean.
- [tex]\mu[/tex] is the value tested at the null hypothesis.
- s is the standard deviation of the sample.
- n is the sample size.
For this problem, the values of the parameters are: [tex]\overline{x} = 29750, \mu = 30000, s = 2500, n = 100[/tex]
Hence, the t-statistic is:
[tex]t = \frac{\overline{x} - \mu}{\frac{s}{\sqrt{n}}}[/tex]
[tex]t = \frac{29750 - 30000}{\frac{2500}{\sqrt{100}}}[/tex]
[tex]t = -1[/tex]
The t-statistic is t = -1.
A similar problem is given at https://brainly.com/question/13873630
