At what temperature (in Kelvin) will the  kinetic energy of 0.3 mole of ‘He’ be the same that of 0.4 mole of argon at 400 K?

Given,number of mole of He, n1=0.3 molnumber of mole of Ar, n2=0.4 molTemperature, T2=400 KTemperature,  T1=? KE=32nRTWhere, R is the gas constantK.E. is the kinetic energy  ⇒32×0.3×R×THelium   =32×0.4×R×400Argon∴T=533.333 K