You can 
put this solution on YOUR website! 
On your TI-83 or 84
Press ON
Press CLEAR
Press 2ND
Press VARS
Press 3   for   3:invNorm(
You see on the screen:
invNorm(
Make it read 
invNorm(.7962)
Press ENTER
See .8281244941
Answer is .8281 if shaded area is to the left, or
-.8281 if shaded area is to the right.
Edwin