Question

B starts after A has gone 1 kilometre and over takes A in 15 minutes walking at a rate of 8 kilometres an hour. Find A's speed.

Answer 1

Here B travel at a speed of 8km/h and B overtake A in 15 Min. So the distance travel B is,
Distance = speed ×time
=8× 15/60=2km
in this quequestion

B starts after A has gone 1 kilometre. Therefore A travel again 1 km for A& B meet at same distance ie,2km
so we can understand A travel 1km takes 15 min therefore A takes 30 minutes for travel 2km
So we can find the speed of A is
Speed= distance/time
=2/(30/60)= 4km/h