There are 60 minutes in an hour so 1 hour 20 minutes = (60+20) minutes = 80 minutes

He will spend a total of 80+10 = <<80+10=90>>90 minutes

90 minutes is = (60/60) hours and 30 minutes = 1 hour 30 minutes = 0130 in 24-hr time

He has to leave 0130 hours earlier than 0900 i.e.

0900-0130 = 0730 hours

# Answer

730
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Pete has to take a 10-minute walk down to the train station and then board a 1hr 20-minute train to LA. When should he leave if he cannot get to LA later than 0900 hours? (24-hr time)
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
730
Pete has to take a 10-minute walk down to the train station and then board a 1hr 20-minute train to LA. When should he leave if he cannot get to LA later than 0900 hours? (24-hr time)
train