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5 votes
5 votes
A thief steals an ATM card and must randomly guess the correct five-digit pin code from a 7-key keypad. Repetition of digits is allowed. What is the probability of a correct guess on the first try?

User SledgeHammer
by
2.8k points

1 Answer

22 votes
22 votes

Answer:

1/(7^5)=1/16807

Explanation:

Assuming 7-key mean zero up to 7,

# of possible codes = 17^5 = 16807

=====

Probability of first try correct = 1/7^5

User Yamilette
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2.3k points