Question

Maria has a debit card with a 4 digit PIN number. Each number can be between 0 and 9. What is the probability that you can figure out her pin number?

Answer 1

The total possible 4 digit pins from the each number between 0 and 9 is,

$\begin{gathered} n(T)=10\cdot10\cdot10\cdot10 \\ =10000 \end{gathered}$

The debit card has only one correct pin. So possibe outcome is,

$n(P)=1$

Determinen the probability for the figure out correct pin is,

$\begin{gathered} P=\frac{n(P)}{n(T)} \\ =\frac{1}{10000} \\ =0.0001 \end{gathered}$

Thus answer is 0.0001 or 1/10000.