Question

Bank of america customers select their own three-digit personal identification number (pin) for use at atms.(b) if zero can be the first digit and the numbers can be repeated, what is the probability mr. jones and mrs. smith select the same pin?

Answer 1

Number of three digit pins possible if zero an be the first digit and the numbers can be repeated is given by

$10^3=1000$

Thus, the probability that Mr Jones and Mrs Smith select the same pin is given by

$\frac{1}{1000} \times \frac{1}{1000} = \frac{1}{1,000,000}$