You have a large jar filled with colored marbles. It contains 1001 blue marbles, 1000 red marbles, and 1000 green marbles.
You randomly draw two marbles out of the jar, then put one or two marbles in (decreasing the total number of marbles in the jar by one or keeping the number constant) using the following rule:
- If the two marbles are blue and green, put a red marble into the jar.
- If the two marbles are green and red, put a red marble into the jar.
- If the two marbles are both red, put two blue marbles into the jar.
- If the two marbles are anything else, put a green marble into the jar.
Repeat this process until one marble remains. What color is it?