Aptitude - Time and Distance - Discussion

@All.

So many of us are confused in where the hell this (150x/100) came from right.

So, my simple explanation is that see the train is 50% faster than car.

Now, consider car speed is X so the train speed will be (X+ 50% of X) Now calculate the train speed.

And you will get (X + 50X/100) = 150X/100.

Hope this helps.

Thanks for explaining the answer.

@All.

The soultion is;

Speed of car = x =>1x=>100/100x.
(All are literally same, in terms of percentage it's 100/100x).
Speed of train = 50%+ x=> (50/100)+(100/100x)=150/100x=3/2x.

I have an easier and simple solution.

The train is 50% faster than a car so for a 75km distance when the train reaches (without stopping) at B car will be some distance behind the train.

Well, train is 50% faster so the car should be at 50km when the train reaches point B (75km) (because 50 + 50% of 50 = 75).

And it's given that the train is 12.5 faster than a car (if it stops for 12.5 min and then after they reach at point B together).

Means rest of the distance (25km) car will cover in 12.5 min.

So, the speed of car = 50km/12. 5/60 hr = 120km/hr.

Thanks everyone for explaining the answer in a better way.

Let speed of car be x km/hr,
100% speed of car is x.
150% speed of train is x/100*150,
= 150x/100.

@Sahil Tiwari.

Thanks for explaining the answer in the simplest way.

It's given that both Car and the train covers 75kms at the same time (t1=t2)
t=d/s

Let's assume car speed as 'x' km/hr.
Train Speed = x + x/2.
=3/2x.

t1=75/x.
t2=75/(3/2)*x.

t1 = t2+12.5mins extra time.
Then solve by converting 12.5 mins to hr by dividing by 60.

@All.

It is just 12.5/60 in the RHS eliminate the 10.
You will get the answer as 120kmph.

T = D/S
T = 75/X-75/1.5X = 12.5/60.