Kenny ran for 40/2=<<40/2=20>>20 hours.

Kenny played basketball for 20/2=<<20/2=10>>10 hours.

# Answer

10
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Kenny played basketball last week. He ran for twice as long as he played basketball, and he practiced on the trumpet for twice as long as he ran. If he practiced on the trumpet for 40 hours, how many hours did Kenny play basketball last week?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
10
Kenny played basketball last week. He ran for twice as long as he played basketball, and he practiced on the trumpet for twice as long as he ran. If he practiced on the trumpet for 40 hours, how many hours did Kenny play basketball last week?
train