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11 votes
11 votes
A thief steals an ATM card and must randomly guess the correct four-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?

The number of possible codes is
(Type an integer or fraction. Simplify your answer.)
The probability that the correct code is given on the first try is
(Type an integer or fraction. Simplify your answer.)

User Sebastian Edelmeier
by
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1 Answer

22 votes
22 votes
The number of possible codes
= 10^4 = 10000

P(correct code on first try)
=1/10000
User Dmitry Sobolevsky
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2.7k points