Aptitude - Time and Distance - Discussion

(The train can travel 50% faster than a car).

This means the train is travelling 1/2 time faster than the car, not 3/2 time faster.

Final Answer: Speed of the car = 100 kmph.

@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.

The train can travel 50% faster than a car. How to define 150 here? Please explain.

Someone help me in this by explaining this.

Can anyone explain to me, how 12.5/60 9is = 5/24?

75/x * 1.5 = 75/x-12.5 (speed of car * 1.5 = speed pf train).
X= 37.5 time taken (min).
Car speed 75/(37.5/60) as time was in mins.

Most Members doubt is how come this speed equation =(3/2)x.
speed =x.

Eg 1:
Car speed =50.
Train speed =>50 + (50/2)=> 50 + 25 = 75
Speed equation => train speed/car speed => 75/50 =3/2.

Ex 2:
Car speed =100.
Train speed =>100+(100/2) => 100 + 50 = 150.
Speed equation =>train speed/car speed => 150/100 = 3/2.

Time equation for train:
However, the train lost about 12.5 minutes while stopping at the stations.
Train's Total Time = Run time + Stopping time.

Convert 12.5 minutes in Hours as follows by 12.5 => 12.5/60 => 125/600 => 25/120 = 5/24.

Want to find the real speed of both the car and the train:
Formula : time = distance/speed.
speed = x.
car = train.
75/x = 75/(3/2)x + 5/24 simplify ->(75/1)*(2/3)->150/3=50/1.
75/x = 50/1x + 5/24 -> 1x and x both are same.
(75/x)-(50/x) = 5/24.
75-50/x = 5/24.
25x = 5/24.
x = 5/24/25, simplify -> (24*25)/5 -> 600/5 -> 120/1.
x= 120/1, don't consider 1.

Answer = 120.

For every 10km he walked, he walked an extra 4km.

So the question is, if he walked an extra 20 km, what would be the actual distance he covers?

Then 10 × 20/4 = 50.

Case1: For car;
D = TV.
75=TV.

Case2:
75={T+(12.5/60)}*1.5V.
75={(60T+12.5)*V}/40.

Now, compare case 1&2.
You get, T = 12.5/20;
As. D = TV.
75 = 12.5/20*V,
V = 120.

The speed of car be x km/h.
Then speed of the train will be = 3x/2km/h,
and the time taken to cover up 75 km is equal, but the train lost about 12.5 minutes while stopping at the stations.
So 75/x - 50/x = 5/24,
x= 120km/h.