Question

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 con- tent of this brand of energy bar. Assume that the dis- tribution of the calorie content is approximately nor- mal.

Answer 1

Answer:

The confidence interval for the true mean calorie content is

$215$

Step-by-step explanation:

In this problem we know the mean and standard deviation fo the sample, so we can compute the CI like this:

$\bar{x}-t*s/\sqrt{n}< \mu$

We need to determine t for 10-1=9 degrees of freedom and 99% confidence level. We look up in the t-table and the value for t is 3.2498.

Then we can calculate the limits of the CI:

$\bar{x}-t*s/\sqrt{n}< \mu$