Question on Lottery Probabilities

[Millacol88]

I have a question on the chances of winning a lottery: If you buy 10 tickets in a lottery where the odds of you winning are 30,000,000 to 1, is your probability of winning 1 in 3,000,000?

 

[SW VandeCarr]

I have a question on the chances of winning a lottery: If you buy 10 tickets in a lottery where the odds of you winning are 30,000,000 to 1, is your probability of winning 1 in 3,000,000?

Yes, pretty close. The odds are not the same as probabilities (p), but with these small odds, it doesn't make much difference. Odds are defined as p/1-p so 10:1 would be p = 0.1/0.9=0.11 In adding independent probabilities there's also a joint probability term that must be subtracted from the sum, but it's negligible in this case and can be ignored.