Pamela's age is two times jiri's age. the sum of their ages is 81. what is jiri's age?

Here is how to solve the given problem above.
Let x be Pamela's age.
and y is Jiri's age.
So x = 2y
and x + y = 81.
Substitute, so 2y + y = 81
3y = 81 << divide each side with 3 and the answer is
y = 27.
x = 2 (27)
x = 54
Therefore, Pamela's age is 54, and Jiri's age is 27.
When you add both ages, you get 81, so it is correct.
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