Some problems have answers. "What are the numbers of arguments that a function takes?", "What is the atomic number of argon gas?"

These problems have answers so they can be referenced and looked up but usually these kinds of problems have to committed to working memory if you want to be efficient and effective in providing solutions. If the answers are not in working memory the concept of these problem have be some where in memory so they can be referenced.

Other problems don't have an answer. There may be several or no right answers. "What's the best way to stop climate change?" "What's the best battery for the an electric car?" "What's the meaning of a Shakespeare play?" There can be lots of constraints and dimensions to these problems. These are interesting problems.

Students need to learn the difference and learn how to use the first kind of problems not to solve the second kind of problem but to be able to think about the interesting problems.