Answer:
The 95% confidence interval for the population mean (calorie count of the snacks bars) is (130.32, 161.68).
Step-by-step explanation:
<em>The question is incomplete:</em>
<em>"A random sample of a specific brand of snack bar is tested for calorie count, with the following results: </em><em>149, 145,140,160,149,153,131,134,153</em><em>. Assume the population standard deviation is </em><em>σ=24</em><em> and that the population is approximately normal. Construct a 95% confidence interval for the calorie count of the snack bars."</em>
We start by calculating the mean of the sample:
We have to calculate a 95% confidence interval for the mean.
The population standard deviation is know and is σ=24.
The sample mean is M=146.
The sample size is N=9.
As σ is known, the standard error of the mean (σM) is calculated as:
The z-value for a 95% confidence interval is z=1.96.
The margin of error (MOE) can be calculated as:
Then, the lower and upper bounds of the confidence interval are:
The 95% confidence interval for the population mean is (130.32, 161.68).