4. drawing a red or blue marble from a bag of
red marbles and blue marbles

If you assume that their are the same number of balls on the bag (red and blue) you should be able to pull 50% of the time red or blue ball no matter the # of balls in the bag so long as they are equil. (Hope this helps,I did my best which the description of the question)

Sure, what you want to talk about?