Hi Recommend Using Your Calculator: Using TI or similarly an inexpensive calculator like an Casio fx-115 ES plus -9999 just a placeholder to far..far left . z (z ≤ -1.99) = normalcdf( -9999, -1.99, 0,1) = .0233 Tables may be used. Recommend Using a Calculator for quick reference. Wish You the Best in your Studies.