Hi,
mean of $35,00 and a standard deviation of $4000
What is the cutoff salary for teachers in the top 10%?
z = NORMSINV(.10) = 1.2816
z = 1.2816 = (X - $35,000)/$4000
$4000*1.2816 + $35,000 = X
$40,126.40 = X, the cutoff salary for teachers in the top 10%