If someone already got the answer kudos to them but I will put my answer here anyway :)
Right, judging from what we know in the question, we know that 5 of the nine participants have been removed from the list leaving us with 4 people remaining. If each of these four people have an equal and unbiased chance of getting picked that is 1/4 chance or 25%.
Itās a bit of a stretch, but hereās my answer:
Initially, all 9 staff members can be picked. Someone is picked at random and 5 options are eliminated, leaving 4 possible candidates. Since there was no bias while picking, the 4 remaining candidates have the same chance of having been picked. The sum of probability of all candidates must be 100%. This leaves 25% for each candidate, or a Ā¼ probability.
However, this answer is way too obvious so I suspect that there is some trickery going on here.
As stated in the question, BFI keeps the winner a secret because he wants to keep up the excitement. But what if BFI himself was the winner? Then the reveal would be disappointing to all the other candidates, especially with the built up hype. Therefore, I suspect that BFI would never let the hype build up this much if he himself was the winner. Thus this scenario would never be possible. From this reasoning, we can conclude that BFI is also definitely not the winner. Leaving 3 possible candidates with a 1/3 probability of being selected. 1/3 final answer.
Is the answer to the quiz 11.11%? Although the 5 people are not being chosen, that doesnāt change the probability that they were selected. Itās still 1 in 9, but if BFI were to get rid of those 5 people and choose again with those 4, the chances would be 25%
Thank you for quote of the month :)
MATHS QUIZ ANWER: 9x - 5x = 4x ( (1/9 = 1x) -5x =4x = 1/4) pi times by the diameter of shreks toe= 100.33563423 rounded to the nearest 100= 100. 1/4 of 100 = (12.5x3/3) x 2 = 25 - NateEh= 12.5, 12.5x 2.58 = 32.25 - the remains of danny DeVitos foot crust = 25%
therefor the answer to this ridiculously hard question must be 25% chance each or 1/4 of a chance each.
I would think 1/4 or 25% chance since there are 4 remainingā¦
yes
I hate probability
But Iām going to say, Its still 1/9 regardless?
Im not the greatest at math but 1/9? Reason the initial chance of being chosen out of the 9 is 1/9 but now that 5 are eliminated, the chance of you correctly guessing who got it is 25%, but the chance of someone being chosen (since it was already chosen) is 1/9
Notesā:star2:
-We start off with 9 people.
-We get informations from BFI01 that tells us 5 people who will NOT be chosen.
We start with a 1 in 9 chance, now having subtracting the 5 away this leaves us with a 1 in 4 chance.
(9-5=4)
Mathā:star2:
KEY:Y=PĆ·X
P=1
X=4
Y=1Ć·4=0.25
Overall there is a 0.25% of being chosen!
I think o_O
80%. 
Some of you guys are on the right track, but unfortunately, no one has solved it completely or convincingly yet. Please keep in mind that you are only allowed to submit one answer, so formulate it carefully. If you give the probabilities, make sure to give a probability for each of the remaining candidates and explain your solution, either with a quick calculation or a convincing logic argument.
Hence, the prize remains to be claimed and everyone who has already submitted an answer above will be unable to win the competition.
Great post as always.
Good luck to everyone trying to get the prize! 
Alright, my answer is abstract and confusing and probably really dumb, but here it is anyway:
Final Answer: McDonalds 1/8 chance
Everyone else 1/3.5 chance
McDonalds will not be told about his chances of winning.
McDonalds chances are 1/8
Everyone elses is 1/3.5.
McDonalds has a 50%(?) chance of still being in the competition. If he is still in the competition, he will have a 1/4 chance. Because he only has a 50% chance of being selected in the first place, he has a 1/8 chance of being the winner.
Everyone else has a 1/3.5 chance of being the winner, as if McDonalds is eliminated it would be 1/3 and if he is not it would be 1/4.
Didnāt want to edit my message to say this in case it eliminates me so:
If anyone finds my answer even slightly logical, feel free to work off of it and see if you can get anything right! Just donāt blame me if you are wrong. ;-)
My workings are all hinged upon the idea that McDonalds has a 50% chance of still being in the competition and Iām very unsure of that.
Iāll have a random guess at the math thing, at first I wouldāve said 25% but I think itās some sort of tricky question.
5/8 are definitely not gonna post it so 3 remaining. BFI didnāt say a thing about Mcdonald his chances so itās not sure if there are 4 remainings. Itād be more logical to have a last of 3 remainings so I think Mcdonalds didnāt make it. With that guess, I think there are 3 people remaining with equally a 1/3 chance which is 33,33333%
Man whoās that widow guy? its pretty dam impressive that he can be #3 on TWO leaderboards in prison at the same time he must be really handsome!
As for the Math competition the problem reminds me of the Monty Hall problem in which there are 3 doors to choose from and after u take ur pick of a door the host reveals that one of the two other doors was indeed incorrect and gives u the chance to swap, swapping doors, in this case, is indeed better as no matter what our initial chance of winning was 1/3 and if u swap it becomes 1/2 so applying the same logic to his problem the chance for BFI, Rose, McDonaldās and Alex being the editor is all 11% and not 25% as BFI did not pick again after telling Mcdonalds the 5 people who were not chosen. I have another idea of what might be the correct solution but heres to hoping this is correct!
There are 9 people in the competition but BFI wouldnt build up hype and take the post himself. That leaves 8 people and he never said they never got a chance of winning, he just said they didnt win. 100% divided by 8 = 12.5
there is a 12.5% of winning if this is truly at random with BFI being drawn out.
12.5% is the answer of everyone winning except BFI with a chance of 0% because truly he didnt put himself in the competition.
Trash the awncer 7.5