单选题 Cars X and Y were traveling together on a straight road at a constant speed of 55 miles per hour when car X stopped for 5 minutes. If car Y continued to travel at 55 miles per hour, how many minutes from the time that car X resumed traveling did it take car X traveling at 60 miles per hour to catch up with car Y? (Assume that the time for car X to slow down and speed up was negligible.)
(A) 5 (B) 30 (C) 45
(D) 55 (E) 60

【正确答案】 D
【答案解析】[解析] 设X经过x分钟后追上Y,根据题意可得: