On your TI-84, press 2nd vars 2, then if your calculator is not old, you
will see:

     lower: -1E99    <-- to get the "E" press 2nd and then the comma key.
     upper:2.45
     μ:0
     σ:1 
     Paste

Select Paste, press enter

If your calculator is old, then make it read

normalcdf(-1E99,2.45,0,1)   

[to get the "E" press 2nd and then the comma key.]

press enter

0.9928571853  <-- round to 0.9929

Edwin

Another way is to go to this site

https://docs.google.com/viewer?a=v&pid=sites&srcid=ZGVmYXVsdGRvbWFpbnxzdGF0aXN0aWNzYW5kb3J8Z3g6MTk3OTBiY2RiYzgxN2Q1Yg

Scroll down till you see 2.4 on the left under the column headed z. 
Then go across to the column headed .05.  The go down that column 
till you're on the same row with 2.4 and you'll read .9929.

Edwin