Bill travels the 400 miles from San Francisco to Los Angeles at 50 mph. Sam travels the same distance at 40 mph. How many more hours than Bill did it take Sam to travel the 400 miles?
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Bill travels the 400 miles from San Francisco to Los Angeles at 50 mph. Sam travels the same distance at 40 mph. How many more hours than Bill did it take Sam to travel the 400 miles?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
2
Bill travels the 400 miles from San Francisco to Los Angeles at 50 mph. Sam travels the same distance at 40 mph. How many more hours than Bill did it take Sam to travel the 400 miles?
train