A Bank Officer Wishes to Study How Many Customers Write

Multiple Choice

A bank officer wishes to study how many customers write bad checks.To accomplish this,the officer randomly selects a weekly sample of 100 checking accounts and records the number that wrote bad checks.The numbers of customers who wrote bad checks in 20 consecutive weekly samples of 100 account holders are,respectively,1,4,9,0,4,6,0,3,8,5,3,5,2,9,4,4,3,6,4,and 0.On the basis of the limits established,if the bank finds that 12 customers in the next weekly sample of 100 account holders have written bad checks,should the bank believe that there has been an unusual variation in the process?

A) Yes
B) No