Code Golf: Shortest code to find a weighted median?

Question

My try at code golfing.

The problem of finding the minimum value of ∑W_i*|X-X_i| reduces to finding the weighted median of a list of x[i] with weights <

Answer 1

Python:

a=sum([[X]*W for X,W in zip(x,w)],[]);l=len(a);a[l/2]+a[(l-1)/2]