The three numbers $2, x$, and 10 have an average of $x$. What is the value of $x$ ?
(A) 5
(B) 4
(C) 7
(D) 8
(E) 6
Since the average of $2, x$ and 10 is $x$, then $\frac{2+x+10}{3}=x$.

Multiplying by 3 , we obtain $2+x+10=3 x$.

Re-arranging, we obtain $x+12=3 x$ and then $2 x=12$ which gives $x=6$.

ANSWER: (E)