A girl goes to her school from her house at a speed of 6km/hr and returns at a speed of 4 km/hr. If she takes 10 hours in going and coming back, the distance between her school and house is Choose the correct choice from the following answers:	A) 12 kms	B) 16 kms	C) 20 kms	D) 24 kms	E) none of above

Rationale: let distance be d 10 = d / 4 + d / 6 answer : d
Answer: D