You have two jars and 100 marbles. Fifty of the marbles are red, and 50 are blue. One of the jars will be chosen at random; then 1 marble will be withdrawn from that jar at random. How do you maximize the chance that a red marble will be chosen? (You must place all 100 marbles in the jars.) What is the chance of selecting a red marble when using your scheme?

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hi hottie ur puzzles r gr8 man…

add some more man..

Sure…

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hey are there any puzzles like marbles

You put one red marble in one jar and the rest in the other one (49 red plus 50 blue). This way you maximize the probability to get a red marble (since you have 1/2 chance of choosing the jar with the red marble and 1/2 of choosing the other one. Then, 100% prob to get the red one if the jar with the red one is chosen and 49/99 chances of getting a red one if you choose the jar with the rest of the marbles).

Namdor,

ya ur answer is correct.. keep it up.. Share good puzzles if u have..