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

Explanation

A `25%` solution by mass means 25 g solute is present in 100 g solution. So, 75 g solute will be present in 300 g solution. In the same way, `40%` solution by mass means 40 g solute is present in 100 g solution. So, 160 g solute will be present in 400 g solution.
Total solute mass `= 160 + 75 = 235 g`
Total solution mass `= 400 + 300 = 700 g`
Percentage solute by mass `=(235)/(700)xx100=33.57%`