Last visit was: 20 Sep 2026, 14:18 It is currently 20 Sep 2026, 14:18
Home
Messages
Tests
Schools
Events
Close
GMAT Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel
Back to Forum
Create Topic
User avatar
krrishabh96
User avatar
Joined: 26 Jun 2023
Last visit: 19 Sep 2026
Posts: 27
Own Kudos:
30
 [2]
Given Kudos: 16
Products:
GMAT Club Tests
Posts: 27
Kudos: 30
 [2]
Trains P and Q started at the same time from stations A and B 18 Sep 2026, 12:10
Kudos
Add Kudos
2
Bookmarks
Bookmark this Post
00:00
Start Timer
Pause Timer
Resume Timer
Show Answer
Hide
Show
History
C
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

45% (medium)

Question Stats:

68% (03:08) correct 32% (02:18) wrong based on 19 sessions

History

Date
Time
Result
Not Attempted Yet
Trains P and Q started at the same time from stations A and B, respectively, and traveled toward each other on parallel tracks, each at its own constant speed. After the trains passed each other, train P took 1 hour to reach station B, and train Q took 4 hours to reach station A. If train Q's speed was 45 kilometers per hour, what is the distance, in kilometers, between stations A and B?

A. 135
B. 225
C. 270
D. 360
E. 450
ShowHide Answer
Official Answer
C
User avatar
MarkGMATMentor
User avatar
Joined: 24 Jul 2018
Last visit: 19 Sep 2026
Posts: 103
Own Kudos:
61
Given Kudos: 38
Location: United States (CA)
GMAT 1: 790 Q51 V50
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
GMAT 1: 790 Q51 V50
Posts: 103
Kudos: 61
Trains P and Q started at the same time from stations A and B 18 Sep 2026, 17:45
Kudos
Add Kudos
Bookmarks
Bookmark this Post
krrishabh96
Trains P and Q started at the same time from stations A and B, respectively, and traveled toward each other on parallel tracks, each at its own constant speed. After the trains passed each other, train P took 1 hour to reach station B, and train Q took 4 hours to reach station A. If train Q's speed was 45 kilometers per hour, what is the distance, in kilometers, between stations A and B?

A. 135
B. 225
C. 270
D. 360
E. 450
Show more
Stay organized on tricky distance / rate problems by using a table and limiting the number of variables.

The unusual part of this problem is that each train has two legs of the journey: from the starting point to the meeting point, and from the meeting point to the end point.

Let's call the meeting point X and set up our table with distance = rate * time and the given information:
D=RT
P: A to X
P: X to B1
Q: B to X45
Q: X to A454

Now we can solve for the distance from X to A (45*4 = 180) and note that it is the same distance from A to X. We also know that the distance from X to B and from B to X is the same (call it d), and that the time for P: A to X and Q: B to X is the same (call it t).

Now you can fill out the rest of the table, noting that the speed for P stays constant at 180/t:
D=RT
P: A to X180=180/tt
P: X to Bd=180/t1
Q: B to Xd=45t
Q: X to A180=454

At this point, it's probably easiest to set d = 180/t and d = 45t equal to each other:
180/t = 45t
\(t^2 = 4\)
t = 2

Since t = 2, d = 45*2 = 90. The total distance is thus 180 + 90 = 270. The answer is C.

On complex rate problems, an organized table can save you from getting lost. Limit yourself to 1 or 2 variables to keep things simple.
User avatar
sxmrenn
User avatar
Joined: 01 Apr 2023
Last visit: 20 Sep 2026
Posts: 7
Given Kudos: 8
Posts: 7
Kudos: 0
Trains P and Q started at the same time from stations A and B 20 Sep 2026, 12:06
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Thank you for this! Is there a faster way to solve this when taking the GMAT?
MarkGMATMentor

Stay organized on tricky distance / rate problems by using a table and limiting the number of variables.

The unusual part of this problem is that each train has two legs of the journey: from the starting point to the meeting point, and from the meeting point to the end point.

Let's call the meeting point X and set up our table with distance = rate * time and the given information:
D=RT
P: A to X
P: X to B1
Q: B to X45
Q: X to A454

Now we can solve for the distance from X to A (45*4 = 180) and note that it is the same distance from A to X. We also know that the distance from X to B and from B to X is the same (call it d), and that the time for P: A to X and Q: B to X is the same (call it t).

Now you can fill out the rest of the table, noting that the speed for P stays constant at 180/t:
D=RT
P: A to X180=180/tt
P: X to Bd=180/t1
Q: B to Xd=45t
Q: X to A180=454

At this point, it's probably easiest to set d = 180/t and d = 45t equal to each other:
180/t = 45t
\(t^2 = 4\)
t = 2

Since t = 2, d = 45*2 = 90. The total distance is thus 180 + 90 = 270. The answer is C.

On complex rate problems, an organized table can save you from getting lost. Limit yourself to 1 or 2 variables to keep things simple.
Show more
Moderator:
Bunuel
Math Expert
113693 posts