A walks at 4 kmph and 4 hours after his start, B cycles after him at 10 kmph. How far from the start does B catch up with A? Choose the correct choice from the following options:	A) 25km	B) 26.7km	C) 30km	D) 32.5km	E) 31.2km
Suppose after x km from the start B catches up with A. Then, the difference in the time taken by A to cover x km and that taken by B to cover x km is 4 hours.   x/4 - x/10 = 4   x = 26.7 km   Answer is 26.7km
<result>B</result>
A walks at 4 kmph and 4 hours after his start, B cycles after him at 10 kmph. How far from the start does B catch up with A?