Probability

1. What is the textbook's definition of probability?
2. If there are 6 green marbles and 4 red marbles in a bag, and you were asked to draw one without looking,
   what is the probability of drawing one green marble?
3. If you don't put that marble back, what is the probability of drawing another green marble?
4. What is the textbook's definition of conditional probability?
5. Using the above "marbles in the bag" scenario, why is this NOT a conditional probability question: What is
   the probability of drawing a red marble and a green marble?
   Solve these problems: There are 5 red marbles and 3 yellow marbles. Two marbles will be drawn, one right
   after the other, and the first marble is NOT put back after it is drawn. There is a single answer to each question.
6. What is the probability of the first draw being a yellow marble and the second draw being a red marble?
   Put all marbles back in the bag (reset).
7. What is the probability of drawing a red marble given that a yellow one was just drawn?
   Put all marbles back in the bag (reset)
8. What is the probability that in the two draws, there is EXACTLY one yellow marble drawn?

Sample Solution