The perimeter of a right triangle is 60 cm. The ratio of the lengths of the three sides of this triangle is 3:4:5. What is the length of the longest side of this triangle in cm?
一个直角三角形的周长是60厘米，这个三角形的三条边长度之比是3：4：5，这个三角形最长的这条边的长度是多少厘米？
<result>25</result>