Question

The heights of American men are normally distributed. If a random sample of American men is taken and the confidence interval is (65.3,73.7), what is the sample mean x¯? Give just a number for your answer. For example, if you found that the sample mean was 12, you would enter 12.

Answer 1

Solution :

given that

Lower confidence interval = 65.3

Upper confidence interval = 73.7

$\bar x$  = (Lower confidence interval + Upper confidence interval ) / 2

$\bar x$ = ( 65.3+ 73.7) / 2

Sample mean = $\bar x$ =69.5