1. Suppose your friends have the following ice cream preferences:

33% of your friends like chocolate (C). The remaining do not like chocolate.

12% of your friends like sprinkles (S) topping. The remaining do not like sprinkles.

6% of your friends like Chocolate (C) and also like sprinkles (S).

Of the friends who like sprinkles, what proportion of this group likes chocolate? (Note: Answers are rounded to four decimal places.)

1. 0.0072
2. 0.0396
3. 0.1818
4. 0.3636
5. 0.5

2. Below is a distribution for number of visits to dentists in one year.

X	1	2	3	4	5
P(X=x)	0.27	0.44	0.18	0.05	0.06

Calculate the following probabilities:

a. P(X < 2) =

b. P(X 3) =

c. P(1< X 3) =

d. P(3 X < 5) =

e. P(3 < X < 5) =

3. A florist determines the probabilities for the number of flower arrangements they deliver each day.

x	19	20	21	22	23
P(x)	0.24	0.23	0.32	0.12	0.09

Find the mean, variance, and standard deviation of the distribution rounded to 4 decimal places.

Mean =

Variance =

Standard Deviation =

Approximately how many arrangements should the florist expect to deliver each week, rounded to the nearest whole number?

4. A certain medical test is known to detect 72% of the people who are afflicted with the disease Y. If 10 people with the disease are administered the test, what is the probability that the test will show that:

All 10 have the disease, rounded to four decimal places?

At least 8 have the disease, rounded to four decimal places?

At most 4 have the disease, rounded to four decimal places?

5. According to government data, 45% of employed women have never been married. Rounding to 4 decimal places, if 15 employed women are randomly selected:

a. What is the probability that exactly 2 of them have never been married?

b. That at most 2 of them have never been married?

c. That at least 13 of them have been married?

6. Assume that 59% of people are left-handed. If we select 5 people at random, find the probability of each outcome described below, rounded to four decimal places:

a. There are some lefties ( 1) among the 5 people.

b. There are exactly 3 lefties in the group.

c. There are at least 4 lefties in the group.

d. There are no more than 2 lefties in the group.

e. How many lefties do you expect?

f. With what standard deviation?

7. In its monthly reports, the local animal shelter states that it currently has 29 dogs and 19 cats available for adoption. 9 of the dogs and 5 of the cats are male. Find each of the following conditional probabilities if an animal shelter is selected at random. Round your answers to two decimal places.

a.The pet is male, given that it is a cat.

b.The pet is a cat, given that it is female.

c.The pet is a female, given that it is a dog.

8. The probabilities that an adult American man has a high blood pressure and/or cholesterol are shown in the table.

Blood Pressure vs. Cholesterol

	BP High	BP OK
Chol. High	0.10	0.27
Chol. OK	0.16	0.47

Round each of the following to two decimal places:

a)What's the probability that a man has both conditions?

b)What's the probability that he has high blood pressure?

c)What's the probability that a man with high blood pressure has high cholesterol?

d)What's the probability that a man has high blood pressure if it's known that he has high cholesterol?

9. In your top dresser drawer are 10 blue and 9 gray socks, unpaired and mixed up. One dark morning you pull two socks from the drawer (without replacement, of course!).

What is the probability that the two socks match? .

Round your answer to 4 decimal places.

10.