If the 20 gram solution is 50% salt, that means there are 10 grams of salt in it before Maya adds the additional 5 grams. Adding 5 grams to 20 grams creates a 25 gram solution with 10 + 5 = 15 grams of salt.
15 grams of salt in a 25 gram solution is 15/25 = 0.6 or 60% salt.
Therefore, after adding 5 grams of salt, Maya has made 25 grams of 60% salt solution.