There are two ropes, the lengths of which are 24 meters and 39 meters, respectively. They must be cut into small pieces of the same length, and there should be no remaining pieces. What is the longest length of each piece of rope?
有两根绳子，长度分别为24米和39米，要把它们截成同样长的小段，不能剩余，每段绳子最长有多少米？
<result>3</result>