The Independent Bank surveyed the status of student accounts
The Independent Bank surveyed the status of student accounts and found that the average overdraft was $24.33 with a standard deviation of $5.87. If the distribution is normal, find the probability of a student being overdrawn by more than $21.69.
P=?
Solution
Normal Distribution
 Mean ( u ) =24.33
 Standard Deviation ( sd )=5.87
 Normal Distribution = Z= X- u / sd ~ N(0,1)                  
 P(X > 21.69) = (21.69-24.33)/5.87
 = -2.64/5.87 = -0.4497
 = P ( Z >-0.45) From Standard Normal Table
 = 0.6736                  

