- #1
Roni1985
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Homework Statement
A has an infinite supply of marbles numbered 1,2,3,... A places the marbles, two at a time and in numerical order, into an urn (i.e. first 1 and 2, then 3 and 4, etc.). Each time A puts two marbles, B reaches in and pulls on out. This process goes on forever.
c) If B always removes marbles randomly (each marble in the urn equally likely to e removed), with what probability will marble number 1 remain in the urn forever?
Homework Equations
The Attempt at a Solution
Here is what I did:
1,2 =>prob that 1 stays is 1/2
1,3,4 => prob that 1 stays is 2/3
1,3,4,6 =>prob that 1 stays is 3/4
until (n-1)/n
so we need to multiply them all and we are left with 1/n
so as n->inf, the probability that it happens is zero ?
Is my answer correct ?
Thanks,
Roni.