In problem solving, whether a mental representation on a problem be appropriate is a crucial point. An expert solver in a particular field is shown in making an adequate representation on a confronted problem based on first impression, sometimes with conviction of a solution. Then, in case of general solvers, the way they construct their mental representation is a remaining question. What kind of causes are left if they are judged inappropriate? In study 1, 13 adults were confronted with Duncker's mountain climbing problem. By an analysis of their initial process of problem solving, it was estimated that the subjects passed intuitive judgments on a proper problem and their judgments were related to their mental representation. So, inappropriate representations might be regarded as taking roots from incorrect intuitive judgments. In study 2, 67 other adults were examined to ascertain the existence of such a relation.