Forgive me if I’m wrong. 25?
First we need to calculate how many years her brother has when she is 18. As text says he is:
18/3 = 6 years old
Now when she gains another 18 years (36-18=18) he will also gain those 18 years
When she is 36 he will have 6+18=24 years old
Answer is 24.
Answer:

Step-by-step explanation:

GIVEN THAT,

LET'S SOLVE NOW

Hope this helps
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