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 19 of 35.
Dip said:
9 years ago
Please anyone can explain me how 125/600 came?
Anonymous said:
9 years ago
Thank u@Prawinn.
Gowtham Sunny said:
9 years ago
Here, Train and car reach at the same time.
So, T1(Car) = T2(train).
Then, T1(Car) = T2(train) + 12.5
So, T1 - T2 = 12.5.
Given Distance = 75,
Let speed be x.
Speed = x -----> Car speed.
Speed = x + 50/100 of x = 3x/2 -----> Train speed.
Therefore, T1 - T2 = 12.5.
75/x - 75/(3x/2) = 12.5 min.
(75 - 150)/x = 12.5/60 hr (Since we are cal in kmph we should convert min to hrs).
x = 120 kmph.
So, T1(Car) = T2(train).
Then, T1(Car) = T2(train) + 12.5
So, T1 - T2 = 12.5.
Given Distance = 75,
Let speed be x.
Speed = x -----> Car speed.
Speed = x + 50/100 of x = 3x/2 -----> Train speed.
Therefore, T1 - T2 = 12.5.
75/x - 75/(3x/2) = 12.5 min.
(75 - 150)/x = 12.5/60 hr (Since we are cal in kmph we should convert min to hrs).
x = 120 kmph.
Amit Chauhan LPU said:
9 years ago
150/100 X it came because.
50% more than X ie :
=> (50/100) * x + x.
==> 150/100 * x.
50% more than X ie :
=> (50/100) * x + x.
==> 150/100 * x.
Kranthi said:
9 years ago
If there is an another method please explain me.
Praveenkumar said:
9 years ago
Hi guys,
Can anyone explain why we are subtracting car speed 75/x from train speed i.e. 75/(3/2)x?
Can anyone explain why we are subtracting car speed 75/x from train speed i.e. 75/(3/2)x?
Tanshi said:
9 years ago
The formula to convert from minutes to hours is:
hours = minutes ÷ 60.
hours = minutes ÷ 60.
Shaheer sheik said:
9 years ago
50% more than x means 50/100 + x = 150/100x.
Ashok said:
9 years ago
Logic is simple guys
Let car speed is x kmph = 100%.
Train speed is 50% more than car speed.
i.e x + 50% of x, 50% of 100% is 50%.
We assume that x = 100% ,so x + 50% will be 150%.
So, speed of train T = 150% of x, i.e (150/100)x, i.e (3/2)x or 3x/2.
We have t = d/s, since they are moving in same direction there difference of d/s is taken and should equal to given time.
ie, (75/x) - (75/(3x/2)) = (12.5/60)hrs (12.5 min to hours).
Solving above equation;
(75/x) - (75 * 2/3x) = 12.5/60.
(3 * 75 - 2 * 75)/3x = 12.5/60.
75/x = 12.5/20.
x = 75 * 20/12.5.
x = 6 * 20 = 120kmph.
Let car speed is x kmph = 100%.
Train speed is 50% more than car speed.
i.e x + 50% of x, 50% of 100% is 50%.
We assume that x = 100% ,so x + 50% will be 150%.
So, speed of train T = 150% of x, i.e (150/100)x, i.e (3/2)x or 3x/2.
We have t = d/s, since they are moving in same direction there difference of d/s is taken and should equal to given time.
ie, (75/x) - (75/(3x/2)) = (12.5/60)hrs (12.5 min to hours).
Solving above equation;
(75/x) - (75 * 2/3x) = 12.5/60.
(3 * 75 - 2 * 75)/3x = 12.5/60.
75/x = 12.5/20.
x = 75 * 20/12.5.
x = 6 * 20 = 120kmph.
Rajeev said:
9 years ago
Actually, here x = (25 x 15)/5?
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