Word Problem

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Cyndi

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I need help with this word problem ASAP!
Train A and Train B are traveling in the same direction on parallel tracks. Train A is traveling at 100 mph and Train B at 120 mph. Train A passes a station at 10:25pm. If Train B passes the same station at 10:40pm at what time will train B catc hup to train A?

If anyone can solve this for me I would appreciate it very much, and I need it yesterday! Thanks a million.

Cyndi
 
HINT: 15 minutes (10:40 - 10:25) is 1/4 hour; 1/4 times 120 = 30 ; so at 10:25, B was 30 miles behind A
 
Use the equation D = R * T

Set up an equation for both.

Train A is D = R * T
D = 100T

Train B is D = R * T
D = 120T But there is a slight adjustment that needs to be made to the distance of train B.


If you consider the station they both pass as the starting point then by the time train B gets there, train A is already miles down the track ( since it got there 15 min. earlier)

For them to cover the same value of D (distance) you have to subtract the amount of extra distance A already covered or add that amount to B’s distance.

Let’s figure out the distance A covers in 15 min…

D = R * T
D = 100 (15/60) since it is in miles per hour, you have to use the units of hours (not min.)

Train A covered 25 miles in 15 min..

So Let train A be D = R * T
D = 100T

And let train B be D + 25 = R * T
D + 25 = 120T ( the adjusted amount of distance between them)

Solve train B’s equation for D, then use substitution to solve for T.

Note : don’t forget that your answer for T is in hours.

So to get the final answer you will need to convert it into minutes and add it to the time B passes the station ( since that was our actual starting point for the equation)
 
The first post says that they are 30 miles apart, but he calculated how far train B would travel in 15 min. At 10:40, train A has travel the extra distance, at a slower rate, so at that instant in time, they are only as far apart as A has traveled (25 miles).
 
alohacharlie said:
The first post says that they are 30 miles apart, but he calculated how far train B would travel in 15 min. At 10:40, train A has travel the extra distance, at a slower rate, so at that instant in time, they are only as far apart as A has traveled (25 miles).
Click to expand...
Charlie, much easier if you situate B 30 miles behind A at 10.25; let x = distance A will travel before B catches up:

x / 100 = (x + 30) / 120 ; leads to x = 150

150 miles @ 100mph = 1.5 hours; 10.25 + 1.30 = 11.55
 
Thanks everybody! Appreciate the help. Waited til the 11th hour because I just found out about this website! I am sure I will be back again soon. Gotta finish my finals by Sunday. Sorry for putting a rush on things but I did not know you all were here til late yesterday when a friend told me. Thanks again,

Cyndi :))
 
I need to know how to translate this word problem into an equation.
a. The sales representative informs you that there are 56 houses for sale with two floor plans still available. Use x to represent floor plan one and y to represent floor plan two. Write an equation that illustrates the situation.
x+y=56
b. The sales representative later indicates that there are three times as many homes available with the second floor plan than the first. Write an equation that illustrates this situation. Use the same variables you used in Part a.
 
paige1923 said:
I need to know how to translate this word problem into an equation.
a. The sales representative informs you that there are 56 houses for sale with two floor plans still available. Use x to represent floor plan one and y to represent floor plan two. Write an equation that illustrates the situation.
x+y=56
b. The sales representative later indicates that there are three times as many homes available with the second floor plan than the first. Write an equation that illustrates this situation. Use the same variables you used in Part a.

This is a duplicate post. Use link below.
Click to expand...

The discussion for Paige is HERE.
 
Cyndi said:
Thanks everybody! Appreciate the help. Waited til the 11th hour because I just found out about this website! I am sure I will be back again soon. Gotta finish my finals by Sunday. Sorry for putting a rush on things but I did not know you all were here til late yesterday when a friend told me. Thanks again,

Cyndi :))
Click to expand...

Was this a problem from your finals?
 
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