Instruction 11-6
as Part of an Evaluation Program,a Sporting Goods

Instruction 11-6
As part of an evaluation program,a sporting goods retailer wanted to compare the downhill coasting speeds of four brands of bicycles.She recorded three trials of each brand and determined their maximum downhill speeds.The results are presented in kilometres per hour in the table below.
$\begin{array}{lcccc}\text { Trial } & \frac{\text { Barth }}{} & \frac{\text { Tomado }}{} & \frac{\text { Reiser }}{} & \frac{\text { Shaw }}{} \\1 & 43 & 37 & 41 & 43 \\2 & 46 & 38 & 45 & 45 \\3 & 43 & 39 & 42 & 46\end{array}$
-Referring to Instruction 11-6,based on the Tukey-Kramer procedure with an overall level of significance of 0.05,the retailer would decide that there is a significant difference between all pairs of mean speeds.