P(-2.14 < z < 0.95) Notice that the shading below starts where z=-2.14 and goes to where z=0.95. We want to know what decimal or percentage of the curve is shaded belowSo by TI-83 or 84 calculator, we press " 2nd " then " vars " then " 2:normalcdf( " [for newer calculators, lower:-2.14, upper:0.95, μ=0; σ=1; paste, enter] For all calculators: normalcdf(-2.14,0.95,0,1) press ENTER 0.8127665627 With tables: [There are two kinds of tables in use today] If your table has negative numbers in the z-column, then find 0.9 in the z-column and go across to the 0.05 column and read 0.8289 find -2.1 in the z-column and go across to the 0.04 column and read 0.0162 Subtract and get 0.8289-0.0162 and get 0.8127 If your table has only positive numbers in the z-column, then find 0.9 in the z-column and go across to the 0.05 column and read 0.3289 find 2.1 in the z-column and go across to the 0.04 column and read 0.4838 Add them and get 0.3289+0.4838 and get 0.8127 Notice that the calculator answers round to 0.8128, whereas with tables you get 0.8127. That's because the calculator is more accurate than tables. Edwin