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SteveDallas · 06-22-2004, 06:43 PM

Yeah that reminds me of a Dilbert strip where Dogbert is selling discount lottery tickets... "they're half price, but the chance of winning is only 1/ in 1,000,000,000 lower." "Hey wait a minute, these are a week old!"

Having said that.... assuming the odds of any one number coming up are identical on each day... you do increase your odds by playing on successive days as compared to playing on just one day. For example let's take a lottery where there are 100 possibilities. Your chance of winning if you play one day are 1%.

Now lets look at two days. The total possible outcomes for those two days are 10,000 (since each day has 100 outcomes and they are independent of each other, you multiply 100 x 100). If you play the same number both days, there are 100 combinations where you win on day 1 (your number on day 1, plus any of the 100 numbers on day 2), and 100 where you win on day 2 (vice versa), for a total of 200--except you subtract one case which you counted twice, the possibility that your number hits on 2 consecutive days. So your odds on scoring either one of the days are 199 out of 10000 or 1.99%.

I'll leave the further iterations as an exercise for the class, because I don't feel like working it out myself.

So yes, playing on successive days increases your chances of winning, but not that much. (You've doubled your investment of cash, but only increased your chances of winning by 99%.)

06-22-2004, 06:43 PM	#5
SteveDallas Your Bartender Join Date: Jan 2002 Location: Philly Burbs, PA Posts: 7,651	Yeah that reminds me of a Dilbert strip where Dogbert is selling discount lottery tickets... "they're half price, but the chance of winning is only 1/ in 1,000,000,000 lower." "Hey wait a minute, these are a week old!" Having said that.... assuming the odds of any one number coming up are identical on each day... you do increase your odds by playing on successive days as compared to playing on just one day. For example let's take a lottery where there are 100 possibilities. Your chance of winning if you play one day are 1%. Now lets look at two days. The total possible outcomes for those two days are 10,000 (since each day has 100 outcomes and they are independent of each other, you multiply 100 x 100). If you play the same number both days, there are 100 combinations where you win on day 1 (your number on day 1, plus any of the 100 numbers on day 2), and 100 where you win on day 2 (vice versa), for a total of 200--except you subtract one case which you counted twice, the possibility that your number hits on 2 consecutive days. So your odds on scoring either one of the days are 199 out of 10000 or 1.99%. I'll leave the further iterations as an exercise for the class, because I don't feel like working it out myself. So yes, playing on successive days increases your chances of winning, but not that much. (You've doubled your investment of cash, but only increased your chances of winning by 99%.)