Is there a math problem that I didn't learn in the sixth grade placement exam?
No, the sixth grade placement exam usually examines students' basic knowledge and ability in mathematics, English and Chinese. They are all math problems they have learned and will not fail in the exam. The sixth grade is between the fifth grade and the seventh grade, and it is also the most important grade and the last grade in the six years of primary school (the May 4th school system is the first grade).