I need help with some Maths.........

   Okay. The odds of flipping a coin and getting the desired result are 50/50, so if someone offers you 10/11 you should tell them too bolt - but if someone offers you 11/10 you should snatch their hand off because over time your guaranteed a profit.

    Applying that logic to the UK National Lottery means that once the Jackpot goes above £14M then you should dive in as you are getting a "value" bet (are you?), but that doesn't give us the full story does it? I say that because the £1 bet we are placing when we buy a lottery ticket, is actually a multiple. We have a series of 3-folds, 4-folds, 5-folds and the big Jackpot bet. I don't know how many bets we have in total, but perhaps only 12p or so from the quid is going towards the Jackpot. Does that mean our "tipping point", when the bet becomes value, is therefore reached long before the Jackpot gets up to £14M?????

   Secondly, how does the Maths apply to the (formerly) Tote Jackpot. In recent months we've seen this rise to several hundred thousand. At what stage does that bet become value?

   Any help would be gratefully appreciated! Tim Harford and the "More or Less" team - are you reading this?