The chances were at 1.7 percent. It was about the same percentage as the chances of the Bulls to make the playoffs this year (at least that what it seemed like). The lottery was installed so that teams would stop tanking games at the end of the season just to get a better draft position. So the worst team doesn't always get the number 1 pick.
The Bulls were not the worst team this season. But over 2/3 of the league was better. The NBA Draft Lottery worked its magic for Chicago and harnessed 1.7% worth of luck to land what could be another turning point in franchise history. They didn't deserve the luck after all the bonehead decisions post Jordan era. Now choosing either Beasley or Rose has a 1.7% chance of not helping the Bulls back into the playoffs. That 1.7% also immediately increased season attendance and revenue by $1.7M within 1.7 minutes. The off season just got 1.7 times more fun for Chicago fans. Ok, I'll stop now.