When $x=2021$, the value of $\frac{4 x}{x+2 x}$ is
(A) $\frac{3}{4}$
(B) $\frac{4}{3}$
(C) 2021
(D) 2
(E) 6
When $x \neq 0$, we obtain $\frac{4 x}{x+2 x}=\frac{4 x}{3 x}=\frac{4}{3}$.

Thus, when $x=2021$, we have $\frac{4 x}{x+2 x}=\frac{4}{3}$.

Alternatively, we could substitute $x=2021$ to obtain $\frac{4 x}{x+2 x}=\frac{8084}{2021+4042}=\frac{8084}{6063}=\frac{4}{3}$.

ANSWER: (B)