Question: concern have the diesel trucks proven to be cost saving...

Concern:

Have the diesel trucks proven to be cost saving?

Information:

Diesel fuel is 12 cents per gallon cheaper than gasoline

Average Truck gets 10 miles per gallon

Diesel trucks cost more to repair and maintain than gasoline trucks.

Data has been collected on 20 trucks with the following information: age, miles driven and type.

“Tony,” said Mike as he put the data in Table 1 in front of Sanchez, “this data shows that, on average the 6 diesel trucks cost $21,156 in R&M expense whereas the 14 gasoline trucks averaged only $13,269 in R&M expense. I am also surprised that simple correlations show a negative relationship between miles driven and age and between miles driven and type of truck.” Tony looked up at Mike and replied, “Mike can I borrow this data. I have a young college graduate that I just hired and she is very bright. Let me ask her to look at this data and see what she comes up with.”

Required:
Assume that you are an analyst working for Tony Sanchez. He has asked you to analyze this data and to address the questions below. Prepare a business memo that addresses his issues.

1. Analyze the data using statistical regression analysis to determine the variables that effect repair and maintenance expense of trucks.

Truck #	Expense	Miles	Years	Type
1	21,100	100,625	1	1
2	23,548	108,750	2	1
3	18,560	83,438	2	1
4	19,525	77,500	3	1
5	22,435	88,125	3	1
6	21,768	85,938	3	1
7	10,345	95,625	1	0
8	11,575	91,875	1	0
9	14,240	98,125	2	0
10	13,300	88,438	2	0
11	14,105	90,625	2	0
12	13,050	81,875	2	0
13	17,150	95,625	3	0
14	11,230	76,849	2	0
15	10,490	92,145	1	0
16	16,645	86,940	3	0
17	16,219	91,257	3	0
18	13,565	85,432	2	0
19	9,245	84,688	1	0
20	14,600	80,625	3	0