An April 15, 2002 report in Time Magazine stated that the average age for women to marry in the United States is now 25.6 years of age. If the standard deviation is assumed to be 4.1 years, find the probability that a random sample of 30 U.S. women would show a mean age at marriage of less than or equal to 24 years. (Give your answer correct to four decimal places.)

Question

An April 15, 2002 report in Time Magazine stated that the average age for women to marry in the United States is now 25.6 years of age. If the standard deviation is assumed to be 4.1 years, find the probability that a random sample of 30 U.S. women would show a mean age at marriage of less than or equal to 24 years. (Give your answer correct to four decimal places.)

Answer 1

Z = (score-mean)/SEm

SEm = SD/√n

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability related to the Z score.