I don't understand statistics very well, but I have a question that I need help with.
Question 1: If there are 11 cards in a pile, and somebody is choosing one at random, what's the chance of them choosing a specific card?
The card goes back into the deck, and the deck is shuffled.
Question 2: A little while later, they pick another another card from the stack of 11. What is the statistical chance of them picking the same card twice?
This is not a joke or a riddle, I am just wondering if someone can explain to me what the answer is and how to find it.
Thank you very much for your help.
Question 1: If there are 11 cards in a pile, and somebody is choosing one at random, what's the chance of them choosing a specific card?
The card goes back into the deck, and the deck is shuffled.
Question 2: A little while later, they pick another another card from the stack of 11. What is the statistical chance of them picking the same card twice?
This is not a joke or a riddle, I am just wondering if someone can explain to me what the answer is and how to find it.
Thank you very much for your help.
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Use multiplication rule for independent events . . .
p(A on 1st draw, and, A on 2nd draw) = p(A on 1st draw)*p(A on 2nd draw) . . .
(1/11)(1/11) = 1/121
p(A on 1st draw, and, A on 2nd draw) = p(A on 1st draw)*p(A on 2nd draw) . . .
(1/11)(1/11) = 1/121