A company sells lottery scratch cards for £1 each. 1% of cards win £50, 20% win £2 and the rest win nothing. Estimate how many cards the company needs to sell to be 99% sure of making an overall profit.
I worked out that the expected gain for the company from a single card sold is 0.1 and the variance is 24.99. Plugging these into CLT I got that the number of cards needs to be bigger than 1,352,376 - does this seem right? Just seems like a big number!