\( = \frac{{{\mu _1}RT}}{V} + \frac{{{\mu _2}RT}}{V}\)
\( = \frac{{{m_1}}}{{{M_1}}}\frac{{RT}}{V} + \frac{{{m_2}}}{{{M_2}}}\frac{{RT}}{V}\)
\( = \frac{8}{{32}}\frac{{RT}}{V} + \frac{7}{{28}}\frac{{RT}}{V} = \frac{{RT}}{{2V}}\)
==> \(10 = \frac{{RT}}{{2V}} …..(i) \)
\(P = \frac{7}{{28}}\frac{{RT}}{V}\)
==> \(P = \frac{{RT}}{{4V}} …..(ii)\)
\(P = 5\,atm\).