$Cr\, | \,Cr^{3+}_{(0.1\,M)}\,||\, Fe^{2+}_{(0.01\, M)}\,|\, Fe$
$=-0.42-(-0.72)-\frac{0.059}{6} \log \frac{(0.1)^{2}}{(0.01)^{3}}$
$=-0.42+0.72-\frac{0.059}{6} \log \frac{0.1 \times 0.1}{0.01 \times 0.01 \times 0.01}$
$=0.3-\frac{0.059}{6} \log \frac{10^{-2}}{10^{-6}}$
$=0.3-\frac{0.059}{6} \times 4$
$=0.30-0.0393=0.26 V$