In a certain lottery 10,000 tickets are sold and ten equal prizes are awarded. What is the probability of not getting a prize if you buy (a) one ticket (b) two tickets (c) 10 tickets.
Total number of tickets sold = 10,000
Number prizes awarded = 10
(i) If we buy one ticket, then
P (getting a prize) = 
P (not getting a prize) = 
(ii) If we buy two tickets, then
Number of tickets not awarded = 10,000 − 10 = 9990
P (not getting a prize) = 9990C2 / 10000C2
(iii) If we buy 10 tickets, then
Number of tickets not awarded = 10,000 − 10 = 9990
P (not getting a prize) = 9990C10 / 10000C10
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