On your TI-84 binomcdf(36,.5,15) gives .2024161226 to get binomcdf( press 2nd then VARS then scroll down to binomcdf( If you have the newer version of TI-84 you will get a screen where you put 36 for the trials, .5 for the p and 15 for the x value. Then go to Paste and binomcdf(36,.5,15) will appear on the screen and press ENTER. Edwin