Probability Practice Tutorial 2011 Name ______

1. Which of the following numbers cannot represent the probability of an event occurring?
A. / / B. / 0 / C. / / D. / 1
2. Each of the 11 letters from the word MATHEMATICS is placed on a separate card. A card is drawn and not replaced. A second card is drawn. What is the probability that the 2 cards chosen are both consonants?
3. A game begins with two cards being dealt from a standard deck of 52 cards. To win this game, the next card dealt fall between them. If the first two cards are a 8 and a Q, what is the probability of winning this game?
4. For each probability experiment the set of all possible outcomes is called
A. / Odds / B. / event / C. / element / D. / sample space
5. Two dart players each throw independently one dart at a target. The probability of each player hitting the bullseye is 0.4 and 0.3 respectively. What is the probability that only one of them will hit the bullseye?

6. A summary of a recent survey is shown below:
25% liked chips
45% like peanuts
10% like both
What percentage liked chips or peanuts?
A. / 40% / B. / 35% / C. / 20% / D. / 10%
7. What is the probability of drawing a spade or a face card in a single random draw from a standard deck of 52 cards?
A. / / B. / / C. / / D. /
8. What is the probability of drawing two clubs in succession in two random draws from a standard deck of 52 cards if the first card is returned,
A. / / B. / / C. / / D. / +-
9. Each letter of the word CANUCKS is placed on a card, as shown below.
These cards are shuffled thoroughly and then placed face down, as shown below.
When all of the cards are turned over, what is the probability that they will spell CANUCKS?
/ / / /

10. Consider a deck of 52 cards. 2 cards are drawn without replacement. Find the probability of

a.  The first is black and the 2nd is a face card



b.  The 2nd is club





c.  The 2nd is black given that the first was the queen of clubs.


11. Machine A produces 70% of a product while Machine B produces 30%. 5% of the production from Machine A is defective, while 8% from Machine B is defective.
a. What is the conditional probability of a product being defective, given that it came from Machine B?


b. If a product is selected, what is the probability that it is defective?





c. If a defective product is selected, what is the probability that it was produced by Machine B?
12. Jar 1 has 3 red, 2 white and 5 black balls. Jar 2 has 4 red, 5 white and 3 black balls. A die is rolled and if a 1 comes up, a ball is selected from Jar 1; however, if another number comes up, a ball is selected from Jar 2.
a) What is the probability of selecting a red ball?





b) Given that the ball selected was red, what is the probability that it came from Jar 1?

14. Consider the following set of grade 12 classes.

Class A / Class B / Class C / Total
Has a Car / 10 / 12 / 6 / 28
Does Not Have A Car / 15 / 18 / 20 / 53
Total / 25 / 30 / 26 / 81

A student is selected at random. Find the probability

a.  That a student is from class B and does not have a car

b.  That a student is from class B, given they do not have a car

c.  That a student does not have a car, given they are from class B

d.  That a student does not have a car.

15. A batter averages 3 hits for every 10 times at bat. What is the probability that she will get exactly 3 hits in her next 8 times at bat?

16. A loaded dice will roll a “1” 85% of the time. What is the probability that in 5 rolls, a 1 is rolled at most 4 times?