Question 6 of 14 , Step 1 of 1
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Kiara sets up a passcode on her tablet, which allows only four-digit codes. A spy sneaks a look at Kiara's tablet and sees her fingerprints on the screen over four numbers. What is the probability the spy is able to unlock the tablet on his first try? Express your answer as a fraction in lowest terms or a decimal rounded to the nearest millionth.

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Step 1 ：The question is asking for the probability that the spy is able to guess the correct four-digit passcode on his first try, given that he knows the four digits Kiara used but not the order.

Step 2 ：The total number of possible four-digit codes is \(4^4\), because each of the four positions can be any of the four digits.

Step 3 ：The number of correct codes is 1, because there is only one correct passcode.

Step 4 ：So the probability is \(\frac{1}{4^4}\).

Step 5 ：total_codes = 256

Step 6 ：correct_codes = 1

Step 7 ：probability = 0.00390625

Step 8 ：Final Answer: The probability that the spy is able to unlock the tablet on his first try is \(\boxed{0.00390625}\).