CIS 125

29 Probability

 

 

1. In how many ways can we select a set of four capacitors from a shipment of 100?

 

 

 

2. If two capacitors in the shipment of 100 are known to be defective, how many ways can we select a set of four non-defective capacitors?

 

 

 

 

3. If two capacitors in the shipment of 100 are known to be defective, how many ways can we select a set of four capacitors such that at least one is defective?

 

 

 

4. If two capacitors in the shipment of 100 are known to be defective, what is the probability of selecting four capacitors with at least one defective unit?

 

 

 

 

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5. A card is selected from an ordinary 52 card desk. What is the probability that the card is the ace of spades?

 

 

 

 

6. A card is selected from an ordinary 52 card desk. What is the probability that the card is a jack?

 

 

 

 

7. Two fair dice are rolled. What is the probability that the sum of the number on the dice is odd?

 

 

 

 

8. Two fair dice are rolled. What is the probability that the sum of the numbers on the dice is 9?

(You may wish to consider verification by exhaustion.)

 

 

 

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For exercises 9-12, an unprepared student takes a 10-question true-false quiz and guesses at the answer to every question.

 

9. What is the probability that the student answers every question correctly?

 

 

 

 

10. What is the probability that the student answers every question incorrectly?

 

 

 

 

11. What is the probability that the student answers exactly one question correctly?

 

 

 

 

12. What is the probability that the student answers exactly five questions correctly?