AMC 12 2010b Problem 10

The average of the numbers $1, 2, 3,\cdots, 98, 99,$ and $x$ is $100x$. What is $x$?

\textbf{(A)}\ \dfrac{49}{101} \textbf{(B)}\ \dfrac{50}{101} \textbf{(C)}\ \dfrac{1}{2} \textbf{(D)}\ \dfrac{51}{101} \textbf{(E)}\ \dfrac{50}{99}