A. To use the telephone banking pay bills the customer has to enter the last three digits of each bill. The numbers 0-9 inclusive can be used. If the numbers happen to be on the same on more one bill the customer has to enter the first three digits as well
What is the probability that a person has 2 bills register with the same last three digits?
last three digits is it like so:
2/ 1000 = 0.002
or is it:
1/ 1000 = 0.001
B. What is the probability that a person with 10 bills to register has at least 2 bills with the same last three digits?
I am not sure?