Question 1163059: A man walking on a railroad bridge is 2/5 of the way along the bridge when he notices a train at a distance approaching at the constant rate of 45 mph . The man can run at a constant rate in either direction to get off the bridge just in time before the train hits him. How fast can the man run?
Answer by ikleyn(52781)   (Show Source):
You can put this solution on YOUR website! .
As the problem is worded, printed, submitted and presented in the post, its formulation is partly incomplete and partly incorrect.
I will not go in details why it is so, and will not make corrections in your post.
I will only notice that accurate formulation and the complete solution to the problem is in the lesson
- A man crossing a bridge and a train coming from behind
in this site.
The problem in that lesson has different numbers, but the method of solution is the same.
So, you actually have an accurate formulation to this problem there, and a TEMPLATE to the solution.
Simply substitute your numbers and follow that template.
The answer to the problem's question is THIS:
ANSWER. The person should run with the velocity of 9 miles per hour ( in any direction along the bridge (!) ).
Read the lesson and have fan (!)
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