Question

Consider the approximately normal population of heights of male college students with mean ì = 69 inches and standard deviation of ó = 4.6 inches. A random sample of 25 heights is obtained
(e) Find P(x > 70). (Give your answer correct to four decimal places.)


(f) Find P(x < 67). (Give your answer correct to four decimal places.)


Not sure how to work these?

Answer 1

Does x = raw score or mean?

If raw score:

Z = (score-mean)/SD

If mean:

Z = (score-mean)/SEm

SEm = SD/√n

In both cases, find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability of Z.

Answer 2

Find the reciprocal of the following number:

-21/23

Answer 3

-21/23=2.50=.9938 or is it 70-69=1over4.6/sqrt25=.92=.8212 for the first one
the second part 67-69=-2over 4.6/sqrt25=.92, -2/.92=-2.17=.0150