Probability puzzle No.2

OK so the other day I was working late and caught the MD having a ‘moment’ with one of the other employees. I decide to cash in on this and I’m running a guess the name of the employee (the sex doesn’t matter in this game but it does in the other) that the MD slept with last night.

I have a board with everyone’s name on it (there are 100 in total) and I’m charging £1 a go.

Having sold 25 goes, i.e. 25 names have been taken by punters, the next person I try to sell one to needs a bit of convincing. I say they stand to win the £100 pot if they guess correctly, giving them a return on their original investment of 9900%.

The person is not convinced and asks me what are his chances of guessing correctly. Apart from being a coniving, malicious t**t, I am also compelled to tell the truth whenever anyone asks me a question. So, what do I tell him in answer to his question of probability?

1% chance of winning still.

75 in 100 chance that the right answer is in his pool of 75.
1 in 75 chance that he picks the right one.

75/100*1/75 = 1/100

just the same as if the 25 hadnt been sold, which intuitively is right.

you should say: ‘I’m sorry I don’t know, maths is not my strong point’.

still 1/100, but only if the chances of the MD sleeping with said strumpet are independent of how attractive they are.

which is obviously true: think of the discrimination lawsuits that would arise from only sleeping with the attractive ones!

Ah yes, but I know the outcome you see, I know the name so I know whether the winning name has been taken or not.

If I’m compelled to tell the truth, what is the probability – the one I see or the one he sees?

schroedingers cat did it.

“schrodingers cat did it”

or will have done it.

It’ll all end in tears….

I say they stand to win the £100 pot if they guess correctly

meaning the 25 already sold are not the recipient of your MD’s affections.

therefore it 1/75? 1.333%?

is this person allowed to pick their own name?

was there only one ‘recipient’ of the MD’s attention on the previous evening?

Too open.

I say they stand to win the £100 pot if they guess correctly

Is the same question as the other 25 where asked. If your honest and the answer has been chosen then they have no chance. If it’s not then they now have a favoured chance of 1/75.

Wouldn’t it just be sooooo funny if this had really happened 😉

It can never be 1 in 100 even at the very beginning if there are 100 employees, as they can rule themselves out immediately.

That only changes if they are the person everyone is trying to guess, in which case the odds are 100%!

In this case, and you know if the correct name has been chosen or not, it will depend:-

Correct name not chosen, their own name still free:- 1/74 or 1
Correct name not chosen, their own namt not free:- 1/75
Correct name already chosen:- 0

It can never be 1 in 100 even at the very beginning if there are 100 employees, as they can rule themselves out immediately.

Good point but he said 100 names not the 100 candidates so could be 1:100