Maths Champion of Askaboutmoney?

[Duke of Marmalade]

https://www.dropbox.com/s/p9kltnf75fmp6un/Lotto.xlsx

Second try

 

[DerKaiser]

Again I agree the number but your reasoning seems all wrong. The chance of a correct line is 1/45C6 and so the chances of an incorrect line is 1-1/45C6. Agreed and this is NCr/(LCs)^r*(1-1/LCs)^(N-r) where:
N is the number of lines submitted by punters (2M)
r is the number of correct entries (6)
L is the panel of Lotto numbers (45), and
s are the number of selections in a line (6)

Spot on Duke - I had the same difficulties.

I know that you can mathematically derive the formula into a relatively simple form:

....but expressing this why this formula works in english is near impossible. I would never start off the explanation with how many different ways you can choose 6 numbers from two million. In other words the formula above is a neat mathematical trick, but you need to start the explanation from first principles to make sense of it.

PS: Like your spreadsheet, sadly I had never used the COMBIN function so that's a useful one to know.

 

[Duke of Marmalade]

Spot on Duke - I had the same difficulties.


PS: Like your spreadsheet, sadly I had never used the COMBIN function so that's a useful one to know.

Great! It got through your firewalls. Did your mother not tell you never to trust a duke