A farmer travelled a distance of 61 km in 9 hours. He travelled partly on foot @ 4 km/hr and partly on bicycle @ 9 km/hr. The distance travelled on foot is:

Answer: Option C

Explanation:

Let the distance travelled on foot be x km.

Then, distance travelled on bicycle = (61 -x) km.

So,	x	+	(61 -x)	= 9
	4		9

9x + 4(61 -x) = 9 x 36

5x = 80

x = 16 km.