Mathematics in daily life, to a large extent is problem solving. Problem solving approach which is core of teaching and learning of Mathematics, depends upon trial and error theory. The errors committed by students cannot be eliminated but reduced to certain extent by studying their causes. Teaching is a process in which a teacher follows various steps out of which two major steps are to discover the errors of students and to provide the remedy for the errors. An attempt was made in the present investigation to study the causes in case of a subject which showed minimum reduction of errors. It was found that the conceptual errors in case of the subject were not reduced.