A man travelled for 13 hours. He covered the first half of the distance at 20 kmph and remaining half of the distance at 25 kmph. Find the distance travelled by the man?
Choose the correct choice from the following options:
A) 168 km	B) 864 km	C) 200 km	D) 240 km	E) 460 km

Rationale: let the distance travelled be x km . total time = ( x / 2 ) / 20 + ( x / 2 ) / 25 = 13 = > x / 40 + x / 50 = 13 = > ( 5 x + 4 x ) / 200 = 13 = > x = 200 km answer : c
Answer: C