A person walks at 5kmph for 6hr and at 4kmph for 12hr.The average speed is. Time and Distance A person walks at 5kmph for 6hr and at 4kmph for 12hr.The average speed is. A. 4 1/3 B. 7 2/3 C. 9 ½ km D. 8km Answer: D. Share this Share on FacebookTweet on TwitterPlus on Google+