Travelling TrainsFrom: Anonymous Date: Sun, 6 Nov 1994 21:06:23 -0700 (MST) Subject: Dr. Math & trains Dr. Math, glad to see that you are on-line. Where were you when I needed you? Is this for real? I received a note saying that you were looking for math questions from students who had math problems. True? I've always wondered about those two trains that left the East coast and the West coast. The question asked when they would meet or where they would meet if both left at the same time and were traveling at 60 to 70 mph. I know that isn't the exact question, but that has always stuck in the back of my mind. Care to try and figure out some kind of reply, even though the question is sort of hazy? Looking forward to hearing from you. I teach Spanish here at Madison Middle School in Albuquerque, New Mexico. Hasta la vista. Brian E. Tafoya Date: Mon, 7 Nov 1994 21:35:07 +0000 From: Elizabeth Anna Weber Hi Brian! Yes, we are for real. Our main patients are K-12 students and their teachers, but thanks for writing to us anyway! If a train leaves the West Coast going at any speed, and another train leaves the East Coast at the same time, going at the same speed, the trains will meet in the middle. The exact meeting point depends on the exact starting points, but it will be somewhere on a line drawn from Texas to the Dakotas. The problem gets a little more complicated when the trains make a few stops, go at different speeds, or when the tracks don't go in a straight line from coast to coast. Elizabeth, Math Doctor on duty. |
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