Question 115
On a circle, 99 natural numbers are written. If $a$ and $b$ are two neighboring numbers on the circle, then $\frac{a}{b}=2$, $a-b=1$ or $a-b=2$. Prove that some number on the circle is divisible by 3.
MathNet 2017-part-01 — 176 problems (EN–VI) Question 115
Math Olympiad Vault · MathNet 2017-part-01 — 176 problems (EN–VI)