When I was 4 years old, my brother was half my age. Now, I’m 18. How old is my brother?
Answer
He is 16 years old.
When I was 4 years old, my brother was 2 years old (half my age), so my brother is 2 years younger than me.
When I am 18 years old, my brother will be 16 years old as he is 2 years younger than me.