Albebra question involving trains.?

Question

Two trains leave New Haven traveling in opposite directions. If one train is traveling 75 miles per hour and they are 405 miles apart after 3 hours, what is the speed of the other train?

please explain because i am trying ot understand this problem and am STUCK!

Answer 1

If one train is doing 75 miles per HOUR, and travelled for 3 HOURS, then 75x3=215 miles it travelled. 405-215=190 miles the other train travelled. Therefore the other train is going 63.33 miles per hour. (190 divided by 3).

Answer 2

This is a fairly simply problem when you break it down.  First, you need to find out how far train #1 (going 75mph) went.  So:



3 hours x 75 mph= 225 miles

Second, you need to know how far train #2 went.  So subtract train #1's  traveled distance from the total miles apart they are after 3 hours:

405 (total miles apart) - 225 (miles traveled by t2) = 180 miles

Now, since you know it traveled 180 miles in 3 hours, divide them and you'll have the average speed of train #2:

180 miles / 3 hours = 60mph

Hope that helped.

Answer 3

This is a trick question. One would assume that when you say the trains are traveling in opposite directions it means the direction of travel is 180 degrees opposed. You did not state that therefore the question cannot be answered. Example. If one train started out traveling in a straight line of 90 degrees and the other started in a straight line of 340 degrees, they are traveling in opposite directions and the answer to the question would be different than if they traveled in a line 180 degrees opposed. Hope that helps!