A man complete a journey in 30 hours. He travels first half of the journey at the rate of 20 km/hr and second half at the rate of 10 km/hr. Find the total journey in km.	Choices:	A) 220 km	B) 224 km	C) 230 km	D) 400 km	E) 234 km
0.5x/20 + 0.5x/10 = 30   --&gt; x/20 + x/10=60   --&gt; 3x = 20x60   --&gt; x = (60x 20)/3 = 400 km.   Answer : 400 km
<result>D</result>
A man complete a journey in 30 hours. He travels first half of the journey at the rate of 20 km/hr and second half at the rate of 10 km/hr. Find the total journey in km.