Question

Bank of America customers select their own three- digit personal identification number (PIN) for use at ATMs.

a. Think of this as an experiment and list four possible outcomes.
b. What is the probability Mr. Jones and Mrs. Smith select the same PIN?
c. Which concept of probability did you use to answer (b)?

Answer 1

#1) Think of this as an experiment and list four possible outcomes.

Answer: There are 3 possible outcomes. The first one is for the condition that the first digit cannot be zero and the digits can be repeated: 9*10*10 = 900. The second outcome is if the digits cannot be repeated: 9*9*8 = 648. The last possible outcome is if zero can be the first digit an the numbers can be repeated: 10*10*10 = 1000. Also the probability of Mr. Jones and Mrs. Smith of selecting the same PIN is 1/900.

I hope it helps, Regards.