Question 1137149
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The probability to guess randomly the correct answer for each question is  {{{1/6}}}.


The probability to guess correctly 3 fixed questions of 5 is  {{{1/6^3}}}.


But there are  {{{C[5]^3}}} = {{{(5*4)/(1*2)}}} = 10  ways to select these 3 questions among the given 5.


So, the final probability is  P = {{{10/6^3}}} = 0.04627 = 4.627%.
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