跪求帮忙 我怎么感觉这题很矛盾

frando

Car X and cay Y ran a 500-kilometer race, What was the average speed of car X?
(1)Car X completed the race in 6 hours and 40 minutes.
(2)Car Y, at an average speed of 100 kilometers per hour, completed the race 1 hour and 40 minutes before car X crossed the finish line.
答案是D. （2）到底什么意思，每小时100，才跑了1 hour and 40 minutes ，怎么就跑完全程了，哪位大哥帮我解释下，谢了！