Solution (source code)

= Solution

The initial position is $k=17$. Applying the <gambler's ruin> <hitting probability> and mean <hitting time> gives
$$
\boxed{\mathbb P(\text{vase survives})=\frac{17}{20},\qquad
\mathbb E[\text{time to fall}]=17(20-17)=51\ \text{minutes}.}
$$
For comparison, the original central starting position $k=10$ would give probability $1/2$ and mean time $100$ minutes.