total internal energy of gases remain same
$u _{1}+ u _{2}= u _{1}^{\prime}+ u _{2}^{\prime}$
$(0.1) C _{ v }(200)+(0.05) C _{ v }(400)=(0.15) C _{ v } T$
$T =\frac{800}{3} k =266.67 k$

Step $1$ It is first compressed adiabatically from volume $8.0 \,m ^{3}$ to $1.0 \,m ^{3}$.
Step $2$ Then expanded isothermally at temperature $T_{1}$ to volume $10.0 \,m ^{3}$.
Step $3$ Then expanded adiabatically to volume $80.0 \,m ^{3}$.
Step $4$ Then compressed isothermally at temperature $T_{2}$ to volume $8.0 \,m ^{3}$.
Then, $T_{1} / T_{2}$ is
(Graphs are schematic and are not to scale)