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Probability question. Please help

A thief steals an ATM card and must randomly guess the correct 5 digit pass code from a 6-Key key pad. Repetition Is allowed. What is the probability of a correct guess on the first try?
 
the number of possible codes
 
the probability that correct code is given on the first try is?  
 
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1 Answer

There are five digits in the pass code:
 
_ _ _ _ _
 
There are only 6 keys in the key pad, so for each digit, your thief has a 1/6 probability of guessing the correct digit. Since digits can be repeated, your thief's 1/6 probability is true across the board:
 
1/6 x 1/6 x 1/6 x 1/6 x 1/6 = 1/7776