Answer:
The test statistic is [tex]t = 3.744[/tex]
Step-by-step explanation:
From the question we are told that
The population mean is [tex]\mu = 140[/tex]
The The level of significance is [tex]\alpha = 0.05[/tex]
The sample size is n = 18
The null hypothesis is [tex]H_o : \mu = 140[/tex]
The alternative hypothesis is [tex]H_a : \mu > 140[/tex]
The sample mean is [tex]\= x = 155[/tex]
The standard deviation is [tex]\sigma = 17[/tex]
Generally the test statistics is mathematically represented as
[tex]t = \frac{\= x - \mu }{ \frac{ \sigma}{ \sqrt{n} } }[/tex]
substituting values
[tex]t = \frac{ 155 - 140 }{ \frac{ 17 }{ \sqrt{18} } }[/tex]
[tex]t = 3.744[/tex]