Exercise 1: Solve then choose the best answer.

Q1. The probability that an event happens is 0.42. What is the probability that the event won't happen?

a) 0.42

b) 0.58

c) 0

d) 1

Q2. When 3 dice are rolled, the sample space consists of how many events?

a) 6

b) 18

c) 36

d) 216

Q3. What is the number of permutations of 6 different objects taken all together?

a) 0

b) 36

c) 1

d) 720

Q4. By evaluating the expression 7 P 3 we get?

a) 21

b) 42

c) 210

d) 256

Q5. The average number of calories in a regular-size burger is 240. If the standard deviation is 38

calories, find the range in which at least 75% of the data will lie. Use Chebyshev's theorem.

a) 126---354

b) 164---316

c) 202---278

d) None of these

Q6. Two Dice are rolled. Find the probability of getting a sum of 8.

a) 7/36

b) 5/36

c) 5/12

d) None of these

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Exercise 2: In a recent survey among 58 students, the following data table were obtained in response

to the question: "If the number of summer classes were increased, would you be more likely to enroll

in one or more of them". (20pts)

If a student is selected at random, find the probability that:

a) The student has the answer: "No Opinion".

b) The student has the answer: "No" given that he is a Freshman student P(No/Freshmen).

c) The student has the answer: "Yes" AND is a Sophomore.

d) That the students has an answer Yes OR Freshman

Exercise 3: One company's ID cards consist of 5 letters followed by 2 digits. How many cards can be

made: (10pts)

a) If repetitions are allowed in both letters and digits?

b) If repetitions are not allowed in both letters and digits?

Exercise 4: A testing lab wishes to test two experimental brands of outdoor paint to see how long each

will last before fading. The testing lab makes 6 gallons of each paint to test. Since different chemical

agents are added to each group and only six cans are involved, these two groups constitute two small

populations. The results (in months) are shown. (28pts)

Brand A

10

60

50

30

40

20

Brand B

35

45

30

35

40

25

a) Find the mean and the standard deviation of brand A.

b) If the mean of brand B = 35 and the standard deviation = 6.5

Which brand is more variable?

c) For brand B: Determine the range then find the z-score of the range

d) Find the percentile rank of 40 months before fading of brand B.

e) Find the value corresponding to the 80th percentile of brand A

EXTRA Exercise: The probability that a person owns a microwave oven is 0.75, that a person owns a

compact disk player is 0.25, and that a person owns both a microwave and a CD player is 0.16. Find the

probability: (Extra pts)

a) That a person owns either a microwave or a CD player.

b) That a person owns microwave given that a CD player.

c) That the person did not own either one.