Benzene be B
Toluene be T
We have made then one lettered to make things easier
[tex]\\ \rm\Rrightarrow \dfrac{P^0_B-P_B}{P^0_B}=x_B[/tex]
[tex]\\ \rm\Rrightarrow 95.1-P_B=95.(0.5)[/tex]
[tex]\\ \rm\Rrightarrow 95.1-P_B=47.55[/tex]
[tex]\\ \rm\Rrightarrow P_B=47.55mmHg[/tex]
And
[tex]\\ \rm\Rrightarrow \dfrac{P^0_T-P_T}{P^0_T}=x_T[/tex]
[tex]\\ \rm\Rrightarrow 28.4-P_T=28.4(0.5)[/tex]
[tex]\\ \rm\Rrightarrow P_T=14.2mmHg[/tex]
Total vapour pressure