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Question
I have a math question.

I have 12 marbles in a container. 3 red, 4 blue, 5 green. How many do I have to take out to get 2 of the same color?

4.
If you draw 2, you could get 2 of the same color but you could also get RB, RG, BG. If you draw 3, you could get 2 of the same color but you could also get RBG. When you draw 4, you could get 2 of any color because you only have 3 color choices and therefore even if the 1st 3 marbles were RBG, the 4th draw would bring R, B, or G giving you several ways to get 2 of the same color. Another way to figure the problem out would be to list all the possibilities and you would see in 4 draws all possibilities have 2 of some color.
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I can answer most questions up through Calculus and some in Number Theory and Abstract Algebra.

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I have had my Bachelor's Degree since 1987 and have been a teacher since 1988. I earned my Masters Degree in Mathematics May 2010. I have been teaching at the same community college since 2002.

Education/Credentials
I have taught 12 years at the community college level, medical college, and technical college as well as a high school instructor and alternative education instructor and charter school instructor.

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Master's GPA 3.56 Bachelor's GPA 3.34 Post grad work not degree related GPA 4.0