There are two different ways we can solve this problem. We could use brute force, or we can use some equations to solve the problem. We can start by defining Pamela and Jiri's ages differently. If Jiri is j, and Pamela is p, we can say that p = j + 8, because Jiri + 8 years is Pamela's age.
Now, using our values for Pamela and Jiri, we can say that (j + 8) + j = 102. Now we just solve like a normal equation, so 2j = 94, and j = 47, so Jiri is 47 years old.