A bus covers half of its journey at a certain speed. In the remaining half-part of the journey, the speed of the bus increased by 50%. The average speed of the bus in the whole journey is what percentage of the speed of the bus in the remaining half-part of the journey?

A bus covers half of its journey at a certain speed. In the remaining half-part of the journey, the speed of the bus increased by 50%. The average speed of the bus in the whole journey is what percentage of the speed of the bus in the remaining half-part of the journey? Correct Answer 80%

GIVEN :

Let the speed of the bus in the first half of the journey be ‘x’ km/hr.

In the remaining half-part, speed of bus increased by 50%,

CALCULATION :

⇒ Speed of bus in remaining half-part of journey = (100 + 50)% of x = 150% of x = 1.5x

Now, if a body travels at two different speeds of ‘a’ km/hr. and ‘b’ km/hr., then the average speed is given as 2ab/(a + b),

Hence,

Average speed of bus in whole journey = (2 × x × 1.5x)/(x + 1.5x) = 1.2x