(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

What is the distribution of stochastic variable X = "the number of attempts needed to find the correct last digit of a pin code"

2. Relevant equations

3. The attempt at a solution

I thought it was like this:

P(X=1) = 1/10

P(X=2) = 9/10*1/9

P(X=3) = 9/10*8/9*1/7

...

...

P(X=10) = 9/10*8/9*7/8*6/7*5/6*4/5*3/4*2/3*1/2*1

Thank you!

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# Homework Help: Probability distribution pin code guessing

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