A sample of 10 diesel trucks were run both hot and cold to

Chapter 5, Problem 6E

(choose chapter or problem)

A sample of 10 diesel trucks were run both hot and cold to estimate the difference in fuel economy. The results, in mpg, are presented in the following table. (From “In-use Emissions from Heavy-Duty Diesel Vehicles,” J. Yanowitz, Ph.D. thesis, Colorado School of Mines, 2001.)

\(\begin{array}{ccc}
\hline \text { Truck } & \text { Hot } & \text { Cold } \\
\hline 1 & 4.56 & 4.26 \\
2 & 4.46 & 4.08 \\
3 & 6.49 & 5.83 \\
4 & 5.37 & 4.96 \\
5 & 6.25 & 5.87 \\
6 & 5.90 & 5.32 \\
7 & 4.12 & 3.92 \\
8 & 3.85 & 3.69 \\
9 & 4.15 & 3.74 \\
10 & 4.69 & 4.19 \\
\hline
\end{array}\)

Find a 98% confidence interval for the difference in mean fuel mileage between hot and cold engines.