### Two Trains Word Problem

Check out Bas Rutten's Liver Shot on MMA Surge: http://bit.ly/MMASurgeEp1 In this video, Mahalo math expert Allison Moffett gives you a word problem about two trains. Question 1: Two Trains --------------------------------------------------------------------- Two trains leave different cities heading towards each other at different speeds. Train A, traveling 70 miles per hour, leaves LA and is heading towards Las Vegas, 260 miles away. At the same time, train B travels from Vegas to LA at 60 miles per hour. Where do the two trains meet? A. 3.7 hoursB. 4 1/3 hoursC. 2 hoursD. 2 1/2 hoursE. 1/2 hour The Correct Answer --------------------------------------------------------------------- If you answered C. 2 hours, you are correct. If you didn't, you can either go back and check your work to try and get the right answer or you can read on to learn how to solve the problem correctly. First, solve for t (time) for train A. To do this, use the formula d=rt, where d is distance, r is rate (speed) and t is time. Train A is traveling at 70 mph, so that gives you d=70t. Divide both sides by 70 to get t=d/70. Now solve for t for train B using the same formula but a different rate of speed. Since train B is traveling in the opposite direction, you'll need to start with the total distance (260 mi). That gives you 260-d=60t. Divide both sides by 60 to get t=(260-d)/60. Now that you have two equations that both equal t, you can set them equal to each other. That gives you?d/70=(260-d)/60. Distribute?the 70 to the parentheses on the right side to get 60d=18,200-70d. Now add 70d to both sides; you're left with 130d=18,200. Divide both sides by 130 and you find that d=140 miles. Plug this number back into train A's original equation (d=70t) and get 140=70t. Divide both sides by 70, and you have your final answer. It will take 2 hours for the trains to meet. Read more by visiting our page at: http://www.mahalo.com/two-trains-word-problem/

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