MathNet 2023-part-03 — 191 problems (EN–VI) Question 54

There are $n \ge 3$ points in a plane. No three points are collinear. Prove one can choose an ordering $P_1, P_2, \dots, P_n$ for these points so that for all $1 \lt i \lt n$ the angle $\angle P_{i-1}P_iP_{i+1}$ is acute.