Question

A) 78 B) 86 C) 89 D) 88 10. The weekly salaries of teachers in one state are normally distributed with a mean of S1100 and a standard deviation of $73. What is the amount of money that separates bottom 8.5% of these teachers? Draw diagram for normal distribution, define the amount of money separating bottom 8.5% of teachers salaries and circle one of the multiple choice answers. (6 points) A) 1020 B) 1000 C) 985 D) 1200

Answer 1

Let, X be the weekly salaries of teachers.

X follows normal distribution with mean $\mu$ = $1100 and standard deviation = $\sigma$= $73

We have to find amount of money that separates bottom 8.5% of these teachers salaries.

That is we have to find x such that P( X <= x ) = 8.5% = 0.085

Using Excel function ,   =NORMINV( Area less than x , $\mu$ , $\sigma$ )

x = NORMINV( 0.085 , 1100, 73 ) = 999.8291 $\approx$1000

Option B is correct.