Aptitude - Problems on Trains - Discussion
Discussion Forum : Problems on Trains - General Questions (Q.No. 14)
14.
Two trains 140 m and 160 m long run at the speed of 60 km/hr and 40 km/hr respectively in opposite directions on parallel tracks. The time (in seconds) which they take to cross each other, is:
Answer: Option
Explanation:
| Relative speed = (60 + 40) km/hr = |  |
100 x | 5 |  m/sec |
= | |
250 | m/sec. |
| 18 | 9 |
Distance covered in crossing each other = (140 + 160) m = 300 m.
| Required time = | |
300 x | 9 | sec |
= | 54 | sec = 10.8 sec. |
| 250 | 5 |
Discussion:
42 comments Page 4 of 5.
Ishita said:
8 years ago
Can we use formula here - a+b/(u+v)?
Pooja said:
8 years ago
How it will come 10.8? Explain me.
(1)
Deepak said:
7 years ago
How it will come 10.8?
Please Explain me.
Please Explain me.
(1)
Yash said:
7 years ago
How it will come 10.8?
Please Explain me.
Please Explain me.
(1)
Javeed khan said:
6 years ago
(100*5%8).
27.7m/s,
140+260 = 300,
300/27.7 =10.8.
27.7m/s,
140+260 = 300,
300/27.7 =10.8.
(1)
Deep said:
6 years ago
Why we calculate 9/250 instead of 250/9?
(2)
Aishi sasmal said:
6 years ago
@Deep.
t = dis/speed.
300/250/9 = 300*9/250.
t = dis/speed.
300/250/9 = 300*9/250.
(1)
Sabikun said:
5 years ago
54/5 = 1.8.
How it could be 10.8.
How it could be 10.8.
Sourabh Sonwane said:
5 years ago
a = 140
b = 160
u = 60km/h
v = 40km/h
u+v = 60 + 40 = 100km/h.
Now convert km/h into m/s then,
100*5/18=27.77.
As we know the formula.
a+b/u + v.
Putting all values in formulas.
140 + 160/27.77 = 10.8.
b = 160
u = 60km/h
v = 40km/h
u+v = 60 + 40 = 100km/h.
Now convert km/h into m/s then,
100*5/18=27.77.
As we know the formula.
a+b/u + v.
Putting all values in formulas.
140 + 160/27.77 = 10.8.
(6)
Syed abbas said:
2 years ago
How is it possible 9/250 and 54/5?
(2)
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