A solution is obtained by mixing 300 g of 25% solution and 400 g of 40% solution by mass. Calculate the mass percentage of the resulting solution.

Explanation

300 g of 25% solution contains solute =`(300 xx 25 )/( 100 ) = 75 g`
400 g of 40% solution contains solute `= (400 xx 40 )/( 100 )`
Total solute = 75 + 160 = 235 g
Total solution = 300 + 400 = 700 g
% of solute in the final solution `=(235)/(700 )xx 100`
= 33.5%
% of water in the final solution = 100 - 33.5
= 65.5%