Solution 1 (Equation):

1, subject condition: there are as many people who guess 3 correctly as there are people who guess 5 correctly. Let's assume that the correct number of people for 3 and 5 is X.

2. Topic conditions: * * * 50 people attend the party, each person guessed at least 2, 5 people guessed right only 2, 9 people guessed right only 4, and 3 people guessed right as many as 5 people. It is also known that the number of people who answered correctly 3 and 5 is X, and the number of people who answered correctly 6 riddles is 50-5-9-2X=36-2X.

3.50 people attended the party, and 202 people got it right. The number of people who guess 2, 3, 4, 5 and 6 is known, and the following equation can be listed:

4. By solving the equation, it can be calculated that the number of people who answered 3 and 5 correctly is 15, so the number of people who answered 6 riddles correctly is:

50-5-9- 15- 15=6 people.

Solution 2 (Hypothesis):

1. Subject condition: Of the 50 people who attended the party, they guessed 202 correctly. It is known that everyone guessed at least two, five people guessed only two, and nine people guessed only four. It is known that people who answered 3, 5 and 6 correctly * *: 50-5-9 = 36 people, and they answered riddle 202-2*5-4*6= 156 correctly.

2, according to the topic conditions: there are as many people who guess 3 and 5. They guessed four riddles correctly on average. Now suppose that all 36 people answered four questions correctly first, and the total number of questions is still 156-36*4= 12. The remaining 12 questions are those who answered six riddles correctly, and no one needs to guess two more. So the number of people who answered the six riddles correctly is: 12/2=6 people.