Word Problem Regarding Time and DistanceDate: 05/30/2002 at 00:30:27 From: Dom LaRue Subject: Word problem regarding time and distance This is our problem of the week and I am stumped as to how to figure out the answer. Here is the question: A train is going through a tunnel that is 650 feet long. The train is traveling 100 feet per second. The train enters the tunnel on one end. Twenty-six seconds later the last car exits the other end of the tunnel. How long is the train? I know that I took 100 feet per second and multiplied it times 26 seconds which is 2600 feet which equals the distance of when the train entered the tunnel and the last car exits the tunnel. I do not know what to do with the tunnel length, whether to add or subtract. Also is there a way to write or describe it algebraically? Thank you for all your help. Date: 05/30/2002 at 09:56:30 From: Doctor Ian Subject: Re: Word problem regarding time and distance Hi Dom, Here is the situation just before the train enters the tunnel, +---------------------+ [][][][][][][>| | +---------------------+ |-------------| 650 ft L where L represents the length of the train. Here is the situation just after the last car exits the tunnel: +---------------------+ | |[][][][][][][> +---------------------+ 650 ft |--------------| L If '[>' is the front of the train, then in 26 seconds it moves (650+L) feet, right? So distance = rate * time (650 + L) ft = (100 ft/sec) * (26 sec) Can you take it from here? - Doctor Ian, The Math Forum http://mathforum.org/dr.math/ Date: 05/31/2002 at 10:01:24 From: Dom LaRue Subject: Thank you (Word problem regarding time and distance) Thank you so much for the prompt reply! It really helped me fully answer the problem for math! |
Search the Dr. Math Library: |
[Privacy Policy] [Terms of Use]
Ask Dr. Math^{TM}
© 1994- The Math Forum at NCTM. All rights reserved.
http://mathforum.org/dr.math/