Answer
$F_0\gt F_{1-α,n_1-1,n_2-1}$: null hypothesis is rejected.
There is enough evidence to conclude that the treatment group have a higher standard deviation for serum retinol concentration than the control group.
Work Step by Step
$s_1,n_1~and~d.f._1$ refer to the treatment group and $s_2,n_2~and~d.f._2$ refer to the control group.
$H_0:~σ_1=σ_2$ versus $H_1:σ_1\gtσ_2$
$F_0=\frac{s_1^2}{s_2^2}=\frac{17.07^2}{6.48^2}=6.94$
$d.f_1=n_1-1=65-1=64$
$d.f_2=n_2-1=65-1=64$
Right-tailed test:
$F_{α,n_1-1,n_2-1}=F_{0.01,64,64}=1.91$
(According to table VIII, for $d.f._1=60$, the closest value to 64, $d.f._2=50$, the closest value to 50, and area in the right tail = 0.01)
Since $F_0\gt F_{1-α,n_1-1,n_2-1}$, we reject the null hypothesis.
