CK-12 Basic Probability and Statistics - A Short Course

(Marvins-Underground-K-12) #1

1.1. Independent Events http://www.ck12.org


Random Sample
A sample in which everyone in a population has an equal chance of being selected; not only is each person or
thing equally likely, but all groups of persons or things are also equally likely.

Venn Diagram
A diagram of overlapping circles that shows the relationships among members of different sets.

Review Questions


Jack is looking for a new car to drive. He goes to the lot and finds a number to choose from. There are three
conditions he is looking for: price, gas mileage, and safety record. He decides to draw a VENN DIAGRAM to
organize all of the vehicles he has found to help him determine what car to pick. Look at the following VENN
DIAGRAM to answer each of the questions 1 through 9.



  1. What is the sample space for Price and Gas Mileage?

  2. What is the sample space for Price and Safety Record?

  3. What is the sample space for Gas Mileage and Safety Record?

  4. What is the sample space for Price or Gas Mileage?

  5. What is the sample space for Price or Safety Record?

  6. What is the sample space for Gas Mileage or Safety Record?

  7. What is the sample space for Price and Gas Mileage and Safety Record?

  8. What is the sample space for Price or Gas Mileage or Safety Record?

  9. Did Jack find the car he was looking for? How can you tell?

  10. If a die is tossed twice, what is the probability of rolling a 4 followed by a 5?

  11. A card is chosen at random from a deck of 52 cards. It is then replaced and a second card is chosen. What is
    the probability of choosing a jack and an eight?

  12. Two cards are drawn from a deck of cards. Determine the probability of each of the following events:
    a. P(heart) or P(club)
    b. P(heart) and P(club)
    c. P(jack) or P(heart)
    d. P(red) or P(ten)

  13. A box contains 5 purple and 8 yellow marbles. What is the probability of successfully drawing, in order, a
    purple marble and then a yellow marble?{Hint: in order means they are not replaced}

  14. A bag contains 4 yellow, 5 red, and 6 blue marbles. What is the probability of drawing, in order, 2 red, 1 blue,
    and 2 yellow marbles?

  15. Fifteen airmen are in the line crew. They must take care of the coffee mess and line shack cleanup. They
    put slips numbered 1 through 15 in a hat and decide that anyone who draws a number divisible by 5 will be
    assigned the coffee mess and anyone who draws a number divisible by 4 will be assigned cleanup. The first
    person draws a 4, the second a 3, and the third and 11. What is the probability that the fourth person to draw
    will be assigned:
    a. the coffee mess?

Free download pdf