Any problems that involve infinity in this manner are not really solvable.
The obvious answer to both of them would be that at the end, the bag contains 9/10 of inifinty, i.e infinity.
However if you look at question 1, you could regard it in this way:
All marbles are going to be put in the bag evenentually....alll marbles are going to come out of the bag, eventually, so the answer could be 0.
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