Q:

A random sample of 10 chocolate energy bars of a certain brand has, on average, 230 calories per bar, with a standard deviation of 15 calories. Construct a 99% confidence interval for the true mean calorie content of this brand of energy bar. Assume that the distribution of the calorie content is approximately normal.

Accepted Solution

A:
Answer:214.389 to 245.611 caloriesStep-by-step explanation:A confidence interval can be constructed as follows:Lower bound (L):[tex]L = X - Z\frac{s}{\sqrt{n}}[/tex]Upper bound (U):[tex]U = X + Z\frac{s}{\sqrt{n}}[/tex]Where 'X' is the sample mean, 's' is the sample standard deviation, 'n' is the sample size, and Z is the x-score associated with the confidence interval.In this problemX = 230; S= 15; n=10; and for a 99% confidence interval, z = 3.291The upper and lower bounds are:[tex]L = 230 - 3.291\frac{15}{\sqrt{10}}\\L= 214.389\\U = 230 + 3.291\frac{15}{\sqrt{10}}\\U= 245.611[/tex]The confidence interval is 214.389 to 245.611 calories.