SOLUTION: Please help me solve this word problem: A train heads strait east at constant speed at 9 am. At noon, a car heads strait east at twice the speed of the train. What time will it

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Question 225806: Please help me solve this word problem:
A train heads strait east at constant speed at 9 am. At noon, a car heads strait east at twice the speed of the train. What time will it be when the car catches up to the train? (We know d=rt, when the two meet, they've gone the same distance. Also, the train travels 3 hours longer than the car since it leaves earlier).

Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
A train heads strait east at constant speed at 9 am. At noon, a car heads strait east at twice the speed of the train. What time will it be when the car catches up to the train?
.
d = rt
.
Let x = speed of train
then
2x = speed of car
.
Let t = hours train was traveling
.
xt = (2x)(t-3)
xt = 2xt-6x
0 = 2xt-6x-xt
0 = xt-6x
0 = x(t-6)
0 = t-6
6 hours = t
.
Car catches up with train at 3 pm.