If you bet 1 on number 13 at roulette or on any other number

If you bet $1 on number 13 at roulette (or on any other number) then you win $35 if that number comes up, an event of probability 1/38, and you lose your dollar otherwise. Suppose you play 70 times. Use the Poisson approximation to estimate the probability that (a) you have won 0 times and lost $70, and (b) you have won 1 time and lost $34, (c) If you win 2 times you have won $2. combine the results of (a) and (b) to conclude that the probability that you will have won more money than you have lost is larger than 1/2.

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