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A.) Grand prize for a lottery is choosing 6 numbers correctly out of 47 (order does not matter). What is the probability of winning this lottery?
B.) If you choose 6 numbers out of 47 and 5 are chosen correctly you win second prize. What is this probability?
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(A) The winning first prize is choosing a subset of 6 numbers correctly from the set of 47 numbers, without looking the order.
P =
=
= 9.31309E-08. ANSWER
(B) To win the second prize, there are
= 6*41 favorable sets of 6 numbers
(indeed, from winning 6 numbers, we can form
= 6 subsets of 5 good numbers and then add
to each of these subsets of 5 good numbers any of remaining 41 BAD numbers).
So, the probability to win the second prize is then
P =
=
=
= 2.29102E-05. ANSWER
Solved.