Problem 663

In the triangles $PQR$ and $STU$, $\angle RPQ = 2 \times \angle UST$, $\angle PRQ = 2 \times \angle SUT$ and $\angle RQP = \frac{1}{5} \times \angle UTS$. How large is $\angle UTS$?

(A) $90^{\circ}$ (B) $100^{\circ}$ (C) $120^{\circ}$ (D) $150^{\circ}$ (E) more information needed