Question

Given a normal distribution with μ  = 101 and σ = 15​, and given you select a sample of n=9​, complete parts​ (a) through​ (d).

What is the probability that Upper X overbar is less than 95?

Answer 1

Solution :

Given that ,

mean = = 101

standard deviation = = 15

n = 9

= 101

=  / n = 15 / 9=5

P( < 95) = P[( - ) / < (95 -101) / 5]

= P(z <-1.2 )

Using z table

= 0.1151