Answer: We reject the null hypothesis and conclude that the treatment group has errors that vary significantly more than the errors of the placebo group.
Step-by-step explanation:
Null hypothesis : Var1 = Var 2
Alternative hypothesis : Var1 > Var 2
The F test statistic is the ratio of squared sample standard deviation:
F= (2.4)^2 / (0.75)^2 = 5,76/ 0,5625 = 10.24
Now we have to get the critical from the F table with degrees of freedom ( n1-1,n2-1)=(23,23) :
From the F table ,F(0.05) = between 2.0050 and 2.0476 .
General rule : if the value of the test statistic is in a rejection region . Reject We reject the Null hypothesis .
F= 10.24 > 2.0476 . Therefore we reject the null hypothesis .
Conclusion: The errors of the treatment group vary more than the error of the placebo group .