Question 1178541
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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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<pre>
(A)  The winning first prize is choosing a subset of 6 numbers correctly from the set of 47 numbers, without looking the order.

          P = {{{1/C[47]^6}}} = {{{1/10737573}}} = 9.31309E-08.         <U>ANSWER</U>



(B)  To win the second prize, there are  {{{C[6]^5*(47-6)}}} = 6*41  favorable sets of 6 numbers

     (indeed, from winning 6 numbers, we can form  {{{C[6]^5}}} = 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 = {{{favorable/total}}} = {{{(6*41)/C[47]^6}}} = {{{(6*41)/10737573}}} = 2.29102E-05.     <U>ANSWER</U>
</pre>

Solved.