1999 Cayley Problem 15

A chocolate drink is 6\% pure chocolate, by volume. If 10 litres of pure milk are added to 50 litres of this drink, the percent of chocolate in the new drink is

\textbf{(A)}\ 5\quad \textbf{(B)}\ 16\quad \textbf{(C)}\ 10\quad \textbf{(D)}\ 3\quad \textbf{(E)}\ 26

If there are no answer choices shown, enter a numerical answer.

Full credit to this problem is given to the CEMC, you may view all Cayley contests here.