Two Gases X and Y have densities dx=3dy and Molecular Masses ,Mx=0.5My. Then, the ratio of their pressures, i.e. Px:Py would be
1/4
1/6
4
6
Densities of two gases are in the ratio 1 : 2 and their temperatures are in the ratio 2 : 1, then the ratio of their respective pressures is