30
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Billy's age is twice Joe's age and the sum of their ages is 45. How old is Billy?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
30
Billy's age is twice Joe's age and the sum of their ages is 45. How old is Billy?
train