If we dissolve 25 grams of salt in 251 grams of water, what is the mass of the resulting solution?

If we dissolve 25 grams of salt in 251 grams of water, then the mass of the resulting solution would be 276 grams. This is in accordance to the Law of Conservation of mass which states that mass cannot be created or destroyed. So, the total mass that goes in a certain process should be the same that would would go out the process. In this case, we have two streams that goes in and one stream going out which would be the solution. The two streams going in should be equal to the stream going out.

Overall mass balance:
25 grams salt + 251 grams water = mass of solution
mass of solution = 276 grams

Perimeter? wheres the answers