For a particular instant lottery, the bettor can determine immediately whether a purchased ticket is a winning ticket. Suppose that the probability of a winning ticket is p=1/10.
a) What is the expected number of tickets that must be purchased in order to find a winning ticket?
b) Find the probability that more than 10 tickets must be purchased to nda winning ticket?
c) Find the probability that exactly 20 tickets must be purchased to nd twowinning tickets?