A person, who can walk down a hill at the rate of 41 km/hour2

A person, who can walk down a
hill at the rate of 4 1 km/hour
2
and up the hill at the rate of 3 km/hour, ascends and comes
down to his starting point in 5 hours. How far did he ascend ?

Let the required distance be x km.

∴	x	+	x	= 5
	9/2		3

⇒ x		2	+	1		= 5
		9		3

⇒ x		2 + 3		= 5
		9

⇒ x =	5 × 9	= 9 km.
	5