IM STUCK! PLS HELP!

Question

Assume that adults have IQ scores that are normally distributed with a mean of 105 and a standard deviation 20. Find P 15, which is the IQ score separating the bottom 15% from the top 85%.

Answer 1

z= (x-105)/20=-1.036

use z tables to find z corresponding to bottom 15%

solve for x

x-105 = -20.72

x= 84.28