Equal weight of CO and CH4 are mixed together in an empty container at 300K. The fraction of total pressure exerted by CH4 is:

Let the weight of CO = weight of CH4 = a g
Moles of CO = a/28
Moles of CH4 = a/16
Total moles = a/28 + a/16
Mole fraction of CH4 = (a/16) / (a/28 + a/16) = (a/16) / (11a/112) = (a/16) * (112/11a) = 112/176 = 7/11
Raoult's law states that the pressure exerted by an individual gas is directly proportional to its mole fraction.
Therefore, the fraction of pressure exerted by CH4 = 7/11
Option A is correct.