Aptitude - Problems on Trains - Discussion

Here, the first train is started at 7:00 am at 20 km/h and the second train started at 8 am at the speed of 25 km/ h.

Train first started at 7 am @ 20 km/h.

7 am to 8 am covers =20 km
8 am to 9 am covers = 40 km
9 am to 10 am covers =60 km
10 am to 11am covers = 80km
11 am to 12 it covers 100 km


Train second started at 8am @ 25 km/h.

8 am to 9 am train covers = 25 km
9 am to 10 am it covers = 50 km
10 am to 11 am it covers = 75 km
11 am to 12 it covers = 100km

Now, both it covers 100 km at 12 o'clock. then how these 2 train meets each other at 10 am please help me, sir.

Why it's taken x-1 but not x+1 because train 2 starts 1 hr later?

@ANISH MISHRA: Let the speed of the train P be xkm/hr and Q be ykm/hr.

After 6hrs, P would have travelled 6xkm (distance=speed*time) and similarly Q would have travelled 6ykm. Given, the distance between P and Q is 528, Hence,

6x + 6y = 528 -> (i).

Also, given that P having travelled 8km/hr more than Q. So,
x = y + 8 -> (ii).

Solving equation (i) & (ii),

x = 48km/hr (speed of train P).
y = 40km/hr (speed of train Q).

@Yuvaraj, Thanks.

If the train was late by 3 hours and 12 minutes, then calculate the nearest hours.

Hi, @Chai.

I got 1:25 PM. Is this correct?

Easy way:

d = 110 km
train A = starts @ 7.00 with speed = 20 km
train B = starts @ 8.00 with speed = 25 km *(5kms difference A & B)

So, A+B=45 kms && d = 110
---> Time = d/s = 110/45 (after cancellation = 22/9)
---> Now add 5 (difference kms between 2 trains speed) to 22 = 27.
---> Now divide 27/9 = 3
---> Add 3 am to 7 am = 10 am.

**Here the difference in time is only 1 hr so added only 5 km's extra.

If the time difference was 2 hrs then we 10 and so on. If the answer you get doesn't match with the options then choose the closest options. The simple reason is time has 60 min where as when you are actually calculating it is of 100. Hope you'll are understanding.

HOPE THIS WORKS I WAS ACTUALLY TRYING TO MAKE SOME EASY SHIT SO THAT THIS TYPE OF SUMS BECOMES EASY FOR THE US :-)

The distance between two stations A and B is 110km.

1st Train starts at 7am at station A at a speed of 20kmph.
i.e. 1st train travels 20 kms in one hour.
Now The distance is 90kms.

2nd train stats at 8am at and travelling at a speed of 25kmph.
So, the Relative speed of two trains is 20 + 25 = 45kmph.
=> Time = Distance/Speed.
Time = 90/45 = 2hrs.
Requied answer is 8 A.M + 2hr =10 A.M.

A train leaves P for Q; at the same time another train leaves Q for P. The trains meet after 6 hours, the train from P and Q having travelled 8 km per hour more than the other. If the distance from P and Q is 528 km, the speed of train from P and Q in km/hour is.

Please solve this?

Here x=3 is answer how to convert into am/pm some other problem.