A travelled from a place P to Q at an average speed of 36 Km/h. He travelled the first 75% of the distance in four-fifth of the time and the rest at a constant speed pf x Km/h. The value of x is :
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 45.
D/T = 36 ⇒ D = 36T
Speed for first part = (3D/4)/(4T/5) = 15D/16T
Speed for second part(x) = (D/4)/(T/5) = 5D/4T
D = 36T
Speed for second part(x) = (5 × 36T)/4T = 180T/4T = 45