Spotify Music

Armaan is creating a playlist on Spotify. There are $s$ total songs in the playlist, of which $w \geq 1$ of them are written by The Weeknd and $b \geq 2$ of them are written by Bruno Mars. You may assume $s \geq w + b$. Armaan orders the songs in the playlist uniformly at random. Find the probability that all of The Weeknd's songs come before the second Bruno Mars song when $w = 8$ and $b = 4$.