a bag contains 8 red marbles,4 green marbles, and 6 blue marbles. How many marbles...

Eva

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a bag contains 8 red marbles,4 green marbles, and 6 blue marbles. How many marbles must you take out to be sure that you have at least 2 marbles of each color?
 
a bag contains 8 red marbles,4 green marbles, and 6 blue marbles. How many marbles must you take out to be sure that you have at least 2 marbles of each color?

If you picked (8+6=) 14 marbles - there is a chance that you have picked 8 red and 6 blue marbles - and no green marble.

Now think ....
 
a bag contains 8 red marbles,4 green marbles, and 6 blue marbles. How many marbles must you take out to be sure that you have at least 2 marbles of each color?

As the question stands the answer's 3, one of each colour, which would leave you 7 reds, 3 greens and 5 blues in the bag. She doesn't say you can't look in the bag to see what colour marbles you're removing, nor does she say whether or not the 'at least 2 marbles of each colour' are IN or OUT of the bag, so if you opened the bag, looked in, took out one of each colour, you'd have the requisite answer in the bag!

If she meant 'at random' and the marbles that count for the answer are those NOT in the bag, she should have said that. I'm not sure which she means but that's the answer as the question stands.

Chris.
 
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