1) there are 80 grams of salt in a 32% solution. find the weight of the solution

2) how much water should be evaporated from a 300 grams of a 20% salt solution to get a 25% salt solution

3) salt was mixed with pure water in a 1: 3 proportion. what is the percentage of salt in the new solution

4) 24 grams of salt and 16 grams of pure water were added to 160 grams of a 35% solution. what is the percentage of salt in the new solution