Answer
$µ_2\neµ_1=µ_3=µ_4$
There is enough evidence to conclude that the mean amount dispensed from the machine II is less than the mean amount dispensed from the machines I, III, IV.
Work Step by Step
In MINITAB, enter the Machine I values in C1, the Machine II values in C2, the Machine III values in C3 and in C4 enter the Machine IV values.
Select Stat -> ANOVA -> One-Way
Select Response data are in a separate column for each factor level.
In Responses enter C1 C2 C3 C4
Click Comparisons. In "Error rate for comparisons" enter 5. In "Comparison procedures assuming equal variances" select Tukey. In "Results" select the 3 options. Click OK.
Click Ok.
