Ajay walks at a speed of 4 km/hr. He doubles his speed after reaching exactly half way. He walks for 12 hours in all. What is the total distance travelled by him?
Answer & explanation
Correct answer: option 3
Assume total distance travelled by Ajay = D
Ajay's speed = 4 km/hr
Reaches a distance of D/2
Time taken T1 = (D/2)/4 = D/8
Ajay doubles his speed = 8 km/hr
now he travels another distance = D/2
Time taken T2 = (D/2)/8 = D/16
Given total time = 12 hours
T1 + T2 = D/8 + D/16 = 12
3D/16 = 12
D = 64
The correct answer is Option (3) → 64 km