If 2 moles of an ideal monatomic gas at temperature To is mixed with 4 moles of another ideal monatomic gas at temperature 2To,then the temperature of the mixture is

Let T be temperature of the mixture.Then U = U1 + U2or    f2(n1+n2)RT = f2(n1)(R)(To)+f2(n2)(R)(2To)or (2+4)T = 2To + 8 To                    (∴ n1 = 2, n2 = 4)∴  T = 53To