Correct Answer - Option 4 : 60
Given:
The length of the first way be
The length of the second way will be
Speed of the train P = s km/hr
Speed of the train Q = (s + 5) km/hr
Formula Used:
Speed = Distance/Time
Calculation:
Suppose the length of the first way be x km and so the length of the second way will be (x + 180) km.
Speed of the train P = s km/hr
Speed of the train Q = (s + 5) km/hr
According to question –
⇒ x/s = 10
⇒ x = 10s ----(i)
Again,
(x + 180)/(s + 5) = 12
⇒ x + 180 = 12(s + 5)
Put the value of x, we have –
⇒ 10s + 180 = 12s + 60
⇒ (12s – 10s) = 180 – 60
⇒ 2s = 120
⇒ s = 60
∴ The speed of the train P is 60 km/hr.