2. 100 200 300 400 Probability Dist n Into to Statistics Jeopardy Probability 500 600 100 200 300 400 500 600 Credits

3. Probability - 100 Answer Which of the following is not a valid probability a.) 2/3 b.) 1/8 c.).70 d.) 5/4

4. Probability - 200 Answer On a multiple choice test with four possible answers for each question, what is the probability of answering a question correctly if you make a random guess? a.) ¼ b.) ¾ c.) ½ d.) 1

5. Probability - 300 Answer A bag contains 4 red marbles, 3 blue marbles, and 5 green marbles. If a marble is randomly selected, what is the probability that it is blue? a.) 1/4 b.) 1/3 c.) 1/5 d.) 1/9

6. Probability - 400 Answer If a person is randomly selected, find the probability that his or her birthday is in May. Ignore leap years. a.) 31/365 b.) 1/31 c.) 1/365 d.) 1/12

7. Probability - 500 Answer An assignment of probability must obey which of the following? a) The probability of any event must be a number between 0 and 1, inclusive. b) The sum of all the probabilities of all outcomes in the sample space must be exactly 1. c) The probability of an event is the sum of the outcomes in the sample space which make up the event. d) All of the above. e) A and B only.

8. Probability - 600 Answer A class consists of 61 students, 10 of which are women. If a student is chosen at random, what is the probability that the student is not a women? a.) 10/61 b.) 1/61 c.) 51/61 d.) 10/51

9. Probability - 100 Answer Which of the following is not a valid probability d.) 5/4 Probabilities are always a value between zero and 1 inclusive. Since 5/4 is greater than 1, it cannot be a valid probability.

10. Probability - 200 Answer On a multiple choice test with four possible answers for each question, what is the probability of answering a question correctly if you make a random guess? a.) ¼ The numerator in our fraction indicates the number of correct choices, the denominator is the total number of choices.

11. Probability - 300 Answer A bag contains 4 red marbles, 3 blue marbles, and 5 green marbles. If a marble is randomly selected, what is the probability that it is blue? a.) 1/4 There are 3 blue marbles out of a total of 12 marbles, so the probability of drawing a blue marble is 4/12 which reduces to 1/4

12. Probability - 400 Answer If a person is randomly selected, find the probability that his or her birthday is in May. Ignore leap years. a.) 31/365 There are 31 days in May out of 365 possible birthdays. (Note: since not all months have the same number of days, we must use days instead of months to find the probability.)

13. Probability - 500 Answer An assignment of probability must obey which of the following? a) The probability of any event must be a number between 0 and 1, inclusive. b) The sum of all the probabilities of all outcomes in the sample space must be exactly 1. c) The probability of an event is the sum of the outcomes in the sample space which make up the event. d) All of the above. a, b, and c are all true statements

14. Probability - 600 Answer A class consists of 61 students, 10 of which are women. If a student is chosen at random, what is the probability that the student is not a women? c.) 51/61 If there are 61 students, 10 of which are women, then there must be 51 (61-10) which are not women. So the probability of not selecting a woman is 51/61

15. Probability Dist n - 100 Answer Determine whether the following is a valid probability distribution X1234 P(x)0.0370.2000.4440.296 a.) Yesb.) No

16. Probability Dist n - 200 Answer Determine whether the following is a valid probability distribution X012345 P(x)0.1290.312-0.0940.0840.1920.375 a.) Yesb.) No

17. Probability Dist n - 300 Answer In a certain town, 60% of adults have a college degree. The accompanying table describes the probability dist n for the number of adults (among 4 randomly selected adults) who have a college degree X01234 P(x)0.02560.15360.3456 0.1296 Find the probability that there are at least 2 with college degrees. a.) 0.3456 b.) 0.8208 c.) 0.4752 d.) 0.5248

18. Probability Dist n - 400 Answer X01234 P(x)0.02560.15360.3456 0.1296 Find the probability that there are less than 3 people who have college degrees. a.) 0.3456 b.) 0.8704 c.) 0.5248 d.) 0.1296

19. Probability Dist n - 500 Answer X01234 P(x)0.02560.15360.3456 0.1296 Find the expected number (the mean number) of people with college degrees from 4 randomly chosen people.

20. Probability Dist n - 600 Answer X01234 P(x)0.02560.15360.3456 0.1296 Find the standard deviation for the number of people who have college degrees out of 4 randomly selected people

21. Probability Dist n - 100 Ans. Determine whether the following is a valid probability distribution X1234 P(x)0.0370.2000.4440.296 b.) No 0 ≤ P(x) ≤ 1—This condition is met ∑ P(x) = 1– The sum of the probabilities =.977 which ≠ 1---so this condition is not met and the dist n is not valid

22. Probability Dist n - 200 Ans. b.) No 0 ≤ P(x) ≤ 1—This condition is not met and the dist n is not valid ∑ P(x) = 1– The sum of the probabilities = 1 X012345 P(x)0.1290.312-0.0940.0840.1920.375 Determine whether the following is a valid probability distribution

23. Probability Dist n - 300 Ans. X01234 P(x)0.02560.15360.3456 0.1296 Find the probability that there are at least 2 with college degrees. b.) 0.8208 The probability of at least 2 having college degrees is found by finding the sum of 2, 3, and 4 having degrees

24. Probability Dist n - 400 Ans. X01234 P(x)0.02560.15360.3456 0.1296 Find the probability that there are less than 3 people who have college degrees. c.) 0.5248 The probability of less than 3 people having college degrees is found by finding the sum of 2, 1, and 0 having degrees=.0256+.1536+.3456

25. Probability Dist n - 500 Ans. X01234 P(x)0.02560.15360.3456 0.1296 To find the expected value (the mean) of the distribution μ x = ∑ x P(x) = 0(.0256) + 1(.1536) + 2(.3456) + 3(.3456) + 4(.1296)= 2.4 TI-Tips: X’s in list 1: P(x) in list 2: 1-var stats L 1, L 2

26. Probability Dist n - 600 Ans. X01234 P(x)0.02560.15360.3456 0.1296 To find the standard deviation: σ=√∑(x-μ) 2 P(x) (0-2.4) 2.0256 + (1-2.4) 2.1536 + (2-2.4) 2.3456 + (3-2.4) 2.3456 + (4-2.4) 2.1296 =.9798

27. Credits Questions have come from the Test Bank for Basic Practice of Statistics And Essentials of Statistics