Mass of one comonent in solution=`((300g)xx25)/100=75g`
Mass of other component in solution= `((400)xx40)/100=160g`
Total mass of solute = `(75 + 160)g = 235 g`
Total mass of solution = `(300 + 400)g = 700 g`
% of solution in the final solution = `((235g))/((700g))xx100=33.57`
% of solvent in the final solution = 100-33.57 =66.43`