The probability of answering three questions correctly is the highest, and this probability is:

Question analysis: solution: let x be the correct number of questions, then x ~ b (12,),

Let P(X=k) be the maximum, (k= 1, 2, ..., 12).

So, what is the solution? So k=3 7 points.

So the probability of answering three questions correctly is the greatest, and the probability is:? 12 point

Comments: This paper mainly investigates the solution of the probability of independent repeated experiments, which belongs to the basic problem.