单选题 A rope 60 meters long is cut into three pieces (A, B, C), If piece A is 12 meters longer than piece B, piece B is 9 meters shorter than piece C, then what is the length, in meters, of the shortest piece?
【正确答案】 E
【答案解析】这是一道极其简单的应用题。设piece B长为x，那么(x+12)+x+(x+9)=60，x=13。E为正确答案。