Answer :
Answer:
The 95% confidence interval is [tex]295.9 < \mu< 324.1[/tex]
A 95% level of confidence mean that there is 95% chance that the true population mean will be in this interval
Step-by-step explanation:
From the question we are told that
The sample size is [tex]n = 25[/tex]
The mean is [tex]\= x = 310 \ mg[/tex]
The standard deviation is [tex]\sigma = 36 \ mg[/tex]
Given that the confidence level is 95% then the level of significance is mathematically represented as
[tex]\alpha = 100 - 95[/tex]
=> [tex]\alpha = 5\%[/tex]
=> [tex]\alpha = 0.05[/tex]
Next we obtain the critical value of [tex]\frac{\alpha }{2}[/tex] from the normal distribution table , the value is
[tex]Z_{\frac{\alpha }{2} } =Z_{\frac{0.05 }{2} } = 1.96[/tex]
Generally the margin of error is mathematically represented as
[tex]E = Z_{\frac{\alpha }{2} } * \frac{\sigma }{\sqrt{n} }[/tex]
substituting values
[tex]E = 1.96 * \frac{36 }{\sqrt{25} }[/tex]
[tex]E = 14.1[/tex]
The 95% level of confidence interval is mathematically represented as
[tex]\= x - E < \mu<\ \= x - E[/tex]
substituting values
[tex]310- 14.1 < \mu< 310+ 14.1[/tex]
[tex]295.9 < \mu< 324.1[/tex]
The 95% level of confidence mean that there is 95% chance that the true population mean will be in this interval