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:
345 comments Page 26 of 35.
Frustrated engineer said:
8 years ago
A train can travel 50% faster than a car.
That means IF CAR SPEED IS X, THEN TRAIN SPEED SHOULD BE 2X. Double speed of car. So how can you guys say 50% more speed?
How this 150x/100 comes?
That means IF CAR SPEED IS X, THEN TRAIN SPEED SHOULD BE 2X. Double speed of car. So how can you guys say 50% more speed?
How this 150x/100 comes?
MikesMatE said:
8 years ago
@ALL.
150x/100 is to say that if the car travelled at x speed which is 100%x=x, then the train was 50% faster than that, 2x is an addition of 100% to x not 50%.
Therefore to add 50% to x would be to add 1/2x which makes it 3/2x.
150x/100 is to say that if the car travelled at x speed which is 100%x=x, then the train was 50% faster than that, 2x is an addition of 100% to x not 50%.
Therefore to add 50% to x would be to add 1/2x which makes it 3/2x.
Loganayaki said:
8 years ago
Car speed is X , and train speed is 50percent faster. Therefore train speed is,
=>car's speed + 50percent of car's speed.
=> x + (50*x)/100,
=>(100x+50x)/100,
=> 150x/100,
=>3x/2 is the speed of train.
=>car's speed + 50percent of car's speed.
=> x + (50*x)/100,
=>(100x+50x)/100,
=> 150x/100,
=>3x/2 is the speed of train.
Arvindra shukla said:
8 years ago
How come 125 and why divided by 60?
Srivishnu said:
8 years ago
It's 12.5 minutes.
To convert it to an hour it should be divided by 60.
i.e 12.5/60 hrs (or)125/(60*10) hrs.
To convert it to an hour it should be divided by 60.
i.e 12.5/60 hrs (or)125/(60*10) hrs.
Dan said:
8 years ago
Train spent extra 12.5 minutes then a car. So we have to subtract bigger time from lesser time to get 12.5. It means that time spent by car must be subtracted from the time taken by car to get the excess time of 12.5 minutes. Thus, it should be like this:
75/(1.5*x)-75/x=0.21 (in hours).
75/(1.5*x)-75/x=0.21 (in hours).
DevB007 said:
7 years ago
Train speed = 50% faster than car speed.
Train speed = car speed + extra 50 % of car speed.
(car speed = X),
(50% extra of X = X/2),
Train speed = X + X/2 = (X/1 + X/2) = (2X+X)/2;
Train speed = 3X/2.
Train speed = car speed + extra 50 % of car speed.
(car speed = X),
(50% extra of X = X/2),
Train speed = X + X/2 = (X/1 + X/2) = (2X+X)/2;
Train speed = 3X/2.
Chinna said:
7 years ago
Here why we used 75/x-75/(3/2)x=125/10*60.
Please anyone can explain me?.
Please anyone can explain me?.
Saggi said:
7 years ago
I think there should be 50/100 not 15/100 right?
Harika ravuri said:
7 years ago
Actually he gave 50% more not 50% times.
so, the speed of train = speed of car + 50% speed of car.
= x+(50/100)*x = 3/2x.
Given that, time of car - time of train = 12.5 min,
(75/x) - (75/(3/2*x)) =125/10 min,
75/x(1 - (2/3)) =125/(10*60) hrs,
1 = 125x/600,
x = 120 kmph.
so, the speed of train = speed of car + 50% speed of car.
= x+(50/100)*x = 3/2x.
Given that, time of car - time of train = 12.5 min,
(75/x) - (75/(3/2*x)) =125/10 min,
75/x(1 - (2/3)) =125/(10*60) hrs,
1 = 125x/600,
x = 120 kmph.
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