Hi Normal Distribution: μ = 30.23 and σ = 13.84 Your Question did not make the trip: This is one example using TI Calculator for You to follow. P(x ≤ 40) = normalcdf(-9999, 40, 13.84, 30.23) = .7599 One could also Use a Casio fx-115ES plus ... inexpensive and easy to use Wish You the Best in your Studies.