if ad is median in triangle abc and bd=24, then cd is:

24.
12.
6.
none of the choices are correct.

To solve this problem, let us first define what a median is. A median is a line segment that connects a vertex and the midpoint of the side opposite to that vertex.

In this case, the vertex is point A while the opposing side is side CB. Since it connects to the midpoint of CB, therefore this means that the median AD equally divides side CB into 2 parts.  Since the length side CB is the sum of the lengths side CD and side BD. Therefore this means that:

length of CD = length of BD

length of CD = 24

 24

I believe the answer is 58, due to the fact that the number in set C is not divisible. Hope this helps, if I am wrong, I am sorry.