Just an idea, sell lottery ticket, 50 cents per ticket and winner gets $5. Need to make some assumptions and do some calculations to figure out the optimal way

Just an idea, sell lottery ticket, 50 cents per ticket and winner gets $5. Need to make some assumptions and do some calculations to figure out the optimal way to price the ticket. Also, we can ask people to buy ticket in advance, then use that money as new prize and lottery that again. Sounds like ponzi, but in fact more like the fractional reserve system our banks use ... not sure whether this will really work, just an idea ...