A thief steals an ATM card and must randomly guess the correct seven​-digit pin code from a 4​-key keypad. Repetition of digits is allowed. What is the probability of a correct guess on the first​ try?

Respuesta :

Answer:

The probability of correct guess on the first​ try is [tex]\frac{1}{16384}[/tex].

Step-by-step explanation:

Consider the provided information.

The ATM has 4 key pad and required a 7 digit pin, where repetition is allowed.

Thief has 7 slots and 4 choices per slot. Because repetition is allowed.

Thus, the total number of different ways are:

4×4×4×4×4×4×4 = 16384

But only one combination is proper code.

Therefore,

[tex]\frac{1}{16384}[/tex]

Hence, the probability of correct guess on the first​ try is [tex]\frac{1}{16384}[/tex].