Question

The average age of child advocates is 34.5 years, with a standard deviation of 24 years. If a county employs 64 child advocates, find the probability that the average age of the group is no less than 29.7 years old.

Answer 1

Solution :

Given that ,

mean = = 34.5

standard deviation = = 24

n = 64

= 34.5

= / n =24 / 64 = 3

P( >29.7 ) = 1 - P( <29.7 )

= 1 - P[( - ) / < (29.7 -34.5) /3 ]

= 1 - P(z < -1.6)

Using z table

= 1 - 0.0548

= 0.9452

probability=0.9452