Assume that the salaries of elementary school teachers in the united states are normally distributed with a mean of $26,000 and a standard deviation of $5000. what is the cutoff salary for teachers in the bottom 10%?
To solve this we would need to find the bottom 10% z-score and find c such that Pr(X<c)=0.1. We find that c = -1.2815 using normal distribution. The cutoff salary for teachers in the bottom 10% would be X=26000 + 5000 x (-1.28155) or 19,592.24.
