A bag contains 12 white and 8 red marbles. A marble is drawn. find the probability that the marble I) white, ii) red, iii)green, iv)white or red.

Back to basics - many probability problems can be simplified by considering the complement of what is asked - and then because those are mutually exclusive outcomes, the two probabilities add to 1 and so a subtraction gives the desired answer.

However, there are two difficulties with regard to this question.

We’re not told if this is with or without replacement
There probably is a mistake and two different colors may have been intended instead of “either a red marble or a red marble

The answer would be $68.04