Question

A technician services mailing machines at companies in the Phoenix area. Depending on the type of malfunction, the service call can take 1, 2, 3, or 4 hours. The different types of malfunctions occur at the same frequency.

If required, round your answers to two decimal places.

a. Develop a probability distribution for the duration of a service call.

x	f(x)
1
2
3
4
total

b. Which of the following probability distribution graphs accurately represents the data set?

1.

2.

3.

- Select your answer -Probability distribution #1Probability distribution #2Probability distribution #3Item 6

c. Consider the required conditions for a discrete probability function, shown below.

Does this probability distribution satisfy equation (5.1)?
- Select your answer -Yes, all probability function values are greater than or equal to 0No, not all probability function values are greater than or equal to 0Item 7

Does this probability distribution satisfy equation (5.2)?
- Select your answer -Yes, the sum of all probability function values equals 1No, the sum of all probability function values does not equal 1Item 8

d. What is the probability a service call will take 3 hours?


e. A service call has just come in, but the type of malfunction is unknown. It is 3:00 P.M. and service technicians usually get off at 5:00 P.M. What is the probability the service technician will have to work overtime to fix the machine today?

Answer 1

a)

x	f(x)
1	0.25
2	0.25
3	0.25
4	0.25

b)

c)Yes, all probability function values are greater than 0 or equal to 1

yes, the sum of all probability function values equals 1

d) probability a service call will take 3 hours =0.25

e)

probability the service technician will have to work overtime to fix the machine today =P(X>2)

=P(X=3)+P(X=4)=0.25+0.25 =0.50