Lottery: Buy two tickets.

[answerbok]

and double your chances of winning. How many of you support this erratic belief. You don't Really believe that do you? Am i then a fool for only buying one? or a bigger fool if i don't buy any? 1 ticket per session? or just one ticket, period??

[Headtime]

Surely, you do double your chances....1 in 14,000,000 plus 1 in 14,000,00 = 2 in 14,000,000.

[WendyW]

Well headtime ... not quite. Each ticket has a 1 in 14,000,000 chance of winning but buying two doesn't halve the odds ... sorry. My view is that we save �2.00 per week now ... may not be much but in a year it does come to �104.

[j2buttonsw]

You are joking WendyW? Two different numbers equals a 2 in 14, 000, 000 chance or 1 in 7, 000, 000. If you bought 14, 000, 000 lottery tickets (or whatever the total number of combinations comes to) each with a different combination you will be guaranteed to win it (the grand prize being only �8 million).

[answerbok]

hurray. a sane person. Correct WendyW - and 14000,000 is a heck of a lot... so is 13,999,999 :-)

[j2buttonsw]

Ah, there is no doubt that 1 in 7 million is still an extremely low chance of winning, in fact you would have to have 1.4 million different lottery tickets to have a 1 in 10 chance of winning but you still halve the odds of winning by buying 2 different lottery tickets. As for me, I have never bought a lottrery ticket for this very reason.

[answerbok]

Headtime, wrong. J2, wrong. - promise me you'll buck up..

[answerbok]

Unless you can fault this reasoning; It does NOT double your chances of winning if you buy 2 tickets.. what so, you buy 2 tickets and your 14mill to 1 becomes 7mill to one?? cor, at that rate you would only need about 25 tickets to get even money odds! Let's not confuse people... Crikey, does AB not have any mathematicians among it's hallowed ranks? Indeed, if you think about it for a moment you will see the folly of your thinking and how buying 2 tickets is not noticeably different than buying one [except you just doubled your investment for no good reason] :-)

[sddsddean]

'Fraid you are wrong Answerbok. You are assuming every time you buy a ticket you halve the odds. This is not so. It just so happens with the second ticket you halve the odds. If you use your theory and buy 25 tickets (assuming all the tickets have different number combinations) you now have a 25 in 14million chance, which is still pretty long odds.

[Squirrel]

Well, if there was a lottery of 10 numbers, and you just needed one of them to be yours to win (1-10), then the chances of winning the jackpot would be 1 in 10. If you bought two tickets, a different number on each, then, obviously your chances would be 2 in 10 (1 in 5) i.e. double the chance that 1 ticket gives. The lottery is no different unless you take the view that "My chances of winning the jackpot were zero in the first place; zero times two is zero."

[answerbok]

read my lips, sddsddean, what you've just done, is agreed with me, [apart from the 'you are wrong' bit].. so we both wrong? No we are right. at the risk of pulling teeth, i won't repeat, so please re-read it. :-) and say where you think i'm wrong, because I didn't say; "every time you buy a ticket you halve the odds". quite the opposite. Wait a minute... this is a windup - right? You all know it doesn't half the odds and you're pulling my leg.. ? :-)

[answerbok]

Or there again, you may have read the first sentence of my Q. literally, and that's my fault for presuming.. [The first sentence is pure sarcasm.] sorry if i misled, just that so many people seem to believe it does half the odds that i was flummoxed and may post this Q. again, in simple, easy to understand words, to try and get an informative answer in simple words; because this thread is getting confusing maybe.

[j2buttonsw]

Nobody said that you halve you chances every time you bought another ticket, only when you buy the second ticket. The third time it goes from 1 in 7, 000, 000 to 1 in 4, 700, 000 then to 1 in 3, 500, 000 etc etc sddsddean is right on the money.

[answerbok]

Okay, slight U-turn for clarification; 2tickets Does double your chance of winning; you now got 2 chances in 14million but, J2, you have not suddenly got 1 chance in 7million okay? everybody happy? except J2.. sorry if i've misunderstood your answer J2 cos you usually know about math n that. :-)

[j2buttonsw]

OK, explain to me how 2 in 14 million is not the same as 1 in 7 million...

[answerbok]

ermm.. i can't, just at the moment, going to soak my head in ice; think i will buy 2 tickets from now on :-)

[j2buttonsw]

I've tried to think about it in a different way: If I had 1 unique number per lottery ticket I would need 14 million of these tickets to guarantee winning, agreed? Now if I had 2 unique numbers per lottery ticket, I would only need 7 million of these new double numbered tickets in order to guarantee winning.

[answerbok]

you are probably right, and i am probably wrong J2; i thought i had it sussed but my brain is fried now. Old age. One thing i realise; "you got to be in it to win it", one ticket puts you in with one astronomical chance, so by that default, buying two or ten or even a hundred tickets is not going to cut a swathe into that unimaginable longshot and you've paid more than you needed to. :-) QED.

[j2buttonsw]

I agree.

[sft42]

odds of winning something and statistical likelyhood are two different things...so 14 mil to 1 and 1 in 14 mil are the same....but buying two tickets changes it.....the statistical likelyhood is 2 in 14,000,000 but the odds are have hardly changed at all (probably something like 13,999,950 to 1 depending on the numbers selected)

[j2buttonsw]

Can we put this one to bed? In this scenario, the odds (or chances) and the stastistical likelyhood are the same thing. No one is giving you a price that the occurence will happen (ie bookmakers odds) it is pure mathematical fact that it is a very unlikely thing for you to win. How you can say that having two unique numbers is equivalent to having a 1 in 13, 999, 950 chance of winning is beyond my comprehension. It may appear as though you have a 1 in 13, 999, 950 chance but you have, in fact, a 1 in 7, 000, 000 chance.