Question

determine the area under the standard normal curve that lies to the left of (a) z=0.92 (b) z=-1.26 (c) z= -0.64 (d) z= -1.09

Answer 1

Your main choices here are (1) a calculator with statistical functions and (2) a table of z-scores.

(a) On my TI-83 Plus calculator I typed in normcdf(-1000, 0.92). The calculator returned the value 0.821. This is approx. 8/10 of the total area under the std normal curve.

(b) I typed in normcdf(-1000, -1.26) and got 0.104

(c) I typed in normcdf(-1000, -0.64) and got 0.261

(d) I typed in normcdf(-1000, -1.09) and got 0.138