contestada

The incomes in a certain large population of college teachers have a normal distribution with mean $75,000 and standard deviation $10,000. sixteen (16) teachers are selected at random from this population to serve on a committee. what is the probability that their average salary is more than $77,500?

Respuesta :

The probability that their average salary;
standard error
= 10,000/sqrt(16)
=10,000/4
= 2500 

(77,500 - 75000)/2500
2,500/2500
= 1 
p (z > 1) = .1587

So, the probability that their average salary is more than $77,500 is 0.1587