Question

In: Statistics and Probability

A report in the Washington Post stated that the average age for men to marry in...

A report in the Washington Post stated that the average age for men to marry in the US is now 28 years of age. If the standard deviation is assumed to be 3.2 years, find the probability that a random sample of 36 U.S. men would show a mean age less than or equal to 27 years?

Solutions

Expert Solution

Solution :

Given that,

mean = = 28

standard deviation = = 3.2

n = 36

= 28

=  / n = 3.2/ 36=0.53333

P( < 27) = P[( - ) / < (27-28) / 0.53333]

= P(z <-1.88 )

Using z table  

= 0.0301   

probability= 0.0301   


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