Challenge DS Problem for GMATT Mondays tonight (3/17)

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Hi all!

Here's a nifty probability question of a type you may not have seen before. If you have trouble solving it -- or can't see how you would even begin -- feel free to swing on by GMATT Mondays tonight, at the link provided in my sig file, where I'll walk you through intuitive approaches to fun, unusual problems like these. (We meet at 4PM Pacific, 7PM Eastern. This week's theme is probability, and there will be eight questions, four PS and four DS; hopefully I'll have time to go through all of them.)

NOTE: Edited the text of the problem (for brevity/clarity).

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A jar contains r red marbles, b blue marbles, and no marbles of any other color. I draw two, at random. Are the odds that the first marble is red greater than the odds that the second marble is red?

1:: r > b > 0
2:: The marbles are drawn without replacement.