The lifetimes of Triple X TV Tubes are approximately normally distributed with mean 13.2 years and standard deviation 3.5 years. Consider the distribution of sample means for all samples of 100 Triple X TV tubes.

Part A

What is the standard error, to two decimal places, of the sample means? Give your answer to two decimal places in the form x.xx

To find the standard error of the sample means, we need to divide the standard deviation of the population by the square root of the sample size.

The standard deviation of the population, σ, is given as 3.5 years. The sample size, n, is 100.

So, the standard error of the sample means (SE) is calculated as:

SE = σ / √n

SE = 3.5 / √100

SE = 3.5 / 10

SE = 0.35

Therefore, the standard error of the sample means is 0.35 years, rounded to two decimal places.

0.33