Aptitude - Time and Distance - Discussion
Discussion Forum : Time and Distance - General Questions (Q.No. 4)
4.
A train can travel 50% faster than a car. Both start from point A at the same time and reach point B 75 kms away from A at the same time. On the way, however, the train lost about 12.5 minutes while stopping at the stations. The speed of the car is:
Answer: Option
Explanation:
Let speed of the car be x kmph.
| Then, speed of the train = | 150 | x | = |  |
3 | x |  kmph. |
| 100 | 2 |
 |
75 | - | 75 | = | 125 |
| x | (3/2)x | 10 x 60 |
 |
75 | - | 50 | = | 5 |
| x | x | 24 |
| x = |
|
25 x24 | |
= 120 kmph. |
| 5 |
Discussion:
344 comments Page 21 of 35.
Yogeshwar yaduwanshi said:
9 years ago
Suppose car speed : x.
Than 50% more speed train : 3x/2.
Than formula car is taken time : 75/x = T....(1).
And train is taken time : 75*2/3x = T-12.5/60....(2).
Both equation solve: x = 120 km/hr.
Than 50% more speed train : 3x/2.
Than formula car is taken time : 75/x = T....(1).
And train is taken time : 75*2/3x = T-12.5/60....(2).
Both equation solve: x = 120 km/hr.
Rakesh said:
10 years ago
If you take speed of train 50/ more than car, let us assume car speed 100 the train speed is 150. Hello Shobha, minutes convert in seconds multiply with 60 SND.
Eleanor said:
10 years ago
@Abhishek Banik.
Can you please explain from the T of car - T of train?
You have lost me there.
Can you please explain from the T of car - T of train?
You have lost me there.
SHOBA said:
10 years ago
Can you explain about 12.5*10/60*10?
Pallavi said:
10 years ago
Can you explain from second step?
Ravi said:
10 years ago
Can you explain please?
Abhishek Banik said:
10 years ago
A to B=75 km.
Distance T = Time.
S = Speed, D = Distance.
Let S of car = x kmph.
S of train = 50% of car speed = x+{(50/100)*x}.
= x+{(1/2)*x}.
= x+x/2 = 3x/2.
T = D/S.
T of car - T of train = 12.5 mins as car speed is low that of train speed.
= 75/x-75/(3x/2) = 12.5/60 (converting 12.5 mins to 12.5/60 hr).
= 75/x-75*2/3x = 12.5/60.
= 75/x-50/x = 12.5/60.
= 25/x = 12.5/60.
x = 25*60/12.5 = 25*60*10/125 = 120.
x = 120 kmph.
Distance T = Time.
S = Speed, D = Distance.
Let S of car = x kmph.
S of train = 50% of car speed = x+{(50/100)*x}.
= x+{(1/2)*x}.
= x+x/2 = 3x/2.
T = D/S.
T of car - T of train = 12.5 mins as car speed is low that of train speed.
= 75/x-75/(3x/2) = 12.5/60 (converting 12.5 mins to 12.5/60 hr).
= 75/x-75*2/3x = 12.5/60.
= 75/x-50/x = 12.5/60.
= 25/x = 12.5/60.
x = 25*60/12.5 = 25*60*10/125 = 120.
x = 120 kmph.
Kishan B said:
10 years ago
Here is simple way of solving this problem.
We have Velocity = Distance/Time.
For car let x be the speed, then speed of the train is 3/2x as per the problem.
Now x = 75/t for car.
1.5x = 75/(t-(5/24)) as train stops for a duration of 5/24 hours.
5/24 obtained by converting 12.5 minute to hour.
Now divide two equations resulting in:
1/1.5 = (24t-5)/24t which upon solving gives t = 0.625.
Put t value in v = d/t where d = 75 km and t = 0.625. Thus you get v = 120 kmph.
Hope this was useful.
We have Velocity = Distance/Time.
For car let x be the speed, then speed of the train is 3/2x as per the problem.
Now x = 75/t for car.
1.5x = 75/(t-(5/24)) as train stops for a duration of 5/24 hours.
5/24 obtained by converting 12.5 minute to hour.
Now divide two equations resulting in:
1/1.5 = (24t-5)/24t which upon solving gives t = 0.625.
Put t value in v = d/t where d = 75 km and t = 0.625. Thus you get v = 120 kmph.
Hope this was useful.
Shyam said:
10 years ago
Can anyone explain in detail?
NITISH GULERIA said:
1 decade ago
Hello friends don't confuse 50% more means x+50% = x+50/100, = x+1/2.
= LCM are 2 and whole equation are 3x/2.
= LCM are 2 and whole equation are 3x/2.
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers