Thermodynamics: JEE Main 2008 Physics question

An insulated container of gas has two chambers separated by an insulating partition. One of the chambers has volume ${V_1}$ and contains ideal gas at pressure ${P_1}$ and temperature ${T_1}$. The other chamber has volume ${V_2}$ and contains ideal gas at pressure ${P_2}$ and temperature ${T_2}$. If the partition is removed without doing any work on the gas, the final equilibrium temperature of the gas in the container will be