The sum of the ages of Kishia and her daughter is 48 years, and the
difference of their ages is 20 years. How old is Kishia?
Let's assume that Kishia's age is x years.
Then, her daughter's age is x-20 years.
The sum of their ages is x + (x-20) = 48.
Combining like terms, we get 2x - 20 = 48.
Adding 20 to both sides gives 2x = 68.
Dividing by 2, we find x = 34.
Therefore, Kishia is 34 years old. Answer: \boxed{34}.