3. Translator (from 6th grade. 1 point). Vasily Petrov is completing an English language assignment. In this assignment, there are 10 English expressions and their Russian translations in random order. The task is to establish the correct correspondences between the expressions and their translations. 1 point is given for each correctly established correspondence. Thus, one can score from 0 to 10 points. Vasya knows nothing, so he chooses the options at random. Find the probability that he will score exactly 9 points.
Solution. It cannot happen that exactly nine correct answers are guessed, because in this case the tenth answer would also be correct. Therefore, the desired probability is zero.

Answer: 0