Aptitude - Time and Distance - Discussion

please explain:

(x+(50/100)*x)= 3x/2

Where 3x/2 & how 150/100?

Please any one can explain the equation [75/x]-[75/1.5x] = [12.5/60].

Let the speed of the car be 10km/h and so as the speed of the train is 50% more ie 50% of 10 is 5 and so the speed of the train can be assumed to be 15km/h. Based on this assumption also this problem can be solved.

Let as take car speed as =100 than train speed is 50% faster than car so 100+50=150.

@Neo, your method is good. I just want to know how you got that 32.5? please elaborate?

Assume the car speed as 120 km/hr.
If cars speed is 120 km/hr then it reaches 75 km in 37.5 min(explained below).

Since 120 km/hr is 120 km/60 min, which is 2 km/1 min.
Therefore for 75 km it takes 37.5 min.


Train speed is 50% higher so it will be 180km/hr.
180 km/hr is 180 km/60 min, which is 3km/min.

Therefore for 75 km it takes 25 min.
It lost 12.5 min in stopping so total time taken by train is (25+12.5) = 37.5 min.

Therefore our assumption is correct. Answer is 120 km/hr.

Let speed of car = c kmph.

So speed of train be c + (50/100)c = (3/2)c.

Time taken by car to cover 75 km distance t1 = 75/c.

Time taken by train to cover 75 km distance t2 = (75*2/3c).

But it is given train lost 12.5 m while stopping at the stations.

So,

Actual time taken by train when stopping at stations to cover 75 km = (75*2/3c) + (12.5/60).

It is given that.

Both start from point A at the same time and reach point B 75 kms away from A at the same time.

75/c = (75*2/3c) + (12.5/60).

c = 120 kmph.

Time taken for car - time taken for train = 5/24 hr.

This equation is derived because both start at same time and end at same time.

Hi guys let me explain in this way.

Given that both reached the distance 75 km at the same time.

That indicates the time taken by car is equal to the time taken by train.

However the time taken by train also includes the delay times due to stations.

Thus,

Train time = distance/speed + 12.5 min (total time).

Cars time = distance/speed (total time).

As distance = 75 km it is clear but.

The speed of train is 50% faster, means 50% more.

If car speed = S then 50% more is.

S+(50/100)S.

Substitute the equation and you can see the answer your self.

Hi, Actually we get speed as 25 only since.

Speed = Distance/(Time x Extra time).

Speed = 25/(125/600) => (25 x 24)/5 = 120.