Number of throws = 50
Success throws = 31
Then 99% confidence interval ,
find for success throws
Probability P is =31/50 = 0.62
Now find mean M = 31
then interval would be
99% of 31 = 30.69
99% of 50 = 49.5
Then , between 49 throws and 51 throws , there will be 31 basket points
Interval is <49, 51>