Borbin the 🐱

PowerBall Mania

04 November, 2022


The Powerball jackpot is approaching another record of

Five numbers 1..69 + one Powerball number from 1..26 is all you need. Chances are 1 in 292 million according to the website.

69 * 68 * 67 * 66 * 65 * 26 = 35.064.160.560 combinations, but since the order doesn't matter (1,2,3,4,5 = 5,4,3,2,1), the probability is much lower. With a set of 5 numbers, there are 5 * 4 * 3 * 2 * 1 possible ways to order the numbers. That is 5! = 120.

The number of possible draws is
35.064.160.560 / 120 = 292.201.338

Rewriting using the factorial expression:
69 * 68 * 67 * 66 * 65 = 69! / 64! = 69! / (69-5)!

Adding the PowerBall with 26 combinations: (69! * 26) / ((69-5)! * 5!) = 292.201.338

Using the binominal coefficient:

The blog doesn't support the markdown math syntax. If, the code for the two math expressions above would be:
$$ \displaystyle {n\choose k}=\frac{n!}{k!(n-k)!} $$
$$ \displaystyle {69\choose 5}*26=\frac{69!}{5!(69-5)!}*26=292.201.338 $$

I have officially purchased 2 tickets to be part of this epic event.


Update

Not only I missed the numbers, everyone else did so too.

Doubled up to continue this epic event.


Update

10 33 41 47 56 10, worth 2 Billion a few days ago.