A person covers 40% of the distance from A to B at 8 km/hr. 40% of the remaining distance at 9 km/hr & the rest at 12 km/hr. His average speed (in km/hr) for the journey is?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 
Let the distance between point A and B be x.
For the 1st part of the journey
For the 2nd part of the journey
=