With this assignment we will work with Discrete Probability Distributions. You should review the rules in your text for finding the mean/Expected value, variance and standard deviation. The template provided will allow you to enter the data and see how the columns are formed and summed. You can then use the results to respond to the questions.

Chapter 5 - Assignment 1

Problem 5-1 Compute the mean and variance of the following probability distribution. Explain what the data and probability of each "x" represents and how it relates to a probability distribution?

x P(x)

5 .1

10 .3

15 .2

20 .4

Problem 5-2: The information below is the number of daily emergency service calls made by the volunteer ambulance service of Walterboro, South Carolina, for the last 50 days. To explain, there were 22 days on which there were 2 emergency calls, and 9 days on which there were 3 emergency calls.

Number of Calls	Frequency
0	6
1	10
2	22
3	9
4	3
Total	50

1. Convert this information on the number of calls to a probability distribution. Note you will need to compute the relative frequency.
2. Is this an example of a discrete or continuous probability distribution? Why?
3. What is the mean number of emergency calls per day?
4. What is the standard deviation of the number of calls made daily?

Problem 5-3: Belk Department Store is having a special sale this weekend. Customers charging purchases of more than $50 to their Belk credit card will be given a special Belk Lottery card. The customer will scratch off the card, which will indicate the amount to be taken off the total amount of the purchase. Listed below are the amount of the prize and the percent of the time that amount will be deducted from the total amount of the purchase.