More Theoretical Probability Problems
1. There are some jelly beans in an Easter basket.
5 are orange, 1 is pink, 3 are purple, and 2 are red. You randomly
select ONE jelly bean from the basket. What is the theoretical probability
that it is
a. pink
b. purple
c. pink or purple
d. pink and purple
2. This time you randomly select a jelly bean, put
it back, and randomly select another. What is the probability that
a. both are purple
b. both are pink
c. the first is pink and the second is purple
3. Same as problem 2 except this time do not replace the first jelly bean.
4. You roll 2 dice and compute the sum. What is
the probability that you get
a. a sum which is a multiple of 4?
b. a sum which is greater than 4?
c. a sum which is a multiple of 4 or greater than
4?
d. a sum which is a multiple of 4 and greater than
4?
5. You are taking a history test consisting of 10 true or false questions. What is the theoretical probability that you get exactly half of the questions correct, if you guess on every question?
6. You are taking an economics test consisting of 8 multiple choice questions. If you guess on every question. what is the theoretical probability that you get all the questions correct? Assume there are 4 choices for each question.
7. Referring to the economics test in problem 6: What is the probability of passing (i.e. getting 5 questions or more correct)?
8. A traveling salesman knows that the probability
of his making a sale is about 40%. He plans to canvass all five houses
on Center Street. What is the probability that
a. he will make 3 or more sales?
b. he makes exactly three sales.
c. he makes sales only at the first three houses.