Question

Kindergarten children have heights that are approximately distributed normal. A random sample of size 20 is taken and the mean x and the standard deviation s are calculated ( x = 40 inches and s = 3).

a. Is there sufficient evidence to indicate that the mean of kindergarten children’ height exceeds 40 inches? Perform a test
using alpha=.05.

b. What is the probability that the mean of kindergarten children’ heights would be between 39 and 42.5 inches?

Answer 1

http://davidmlane.com/hyperstat/z_table.html