A Construction of a Diagnostic Test for Mathematical Problems Solving in The Greatest Common Divisor and Least Common Multiple for Grade 6 Students

Abstract

In this thesis, the researcher constructs (1) A mathematical problem-solving diagnostic test on the greatest common divisor and least common multiple; and analyzes (2) The deficiencies in mathematical problem solving on the greatest common divisor and least common multiple for the students under study. The sample population consisted of 295 grade 6 students at schools under the Bangkok Metropolitan Administration, Suan Luang District Office in the academic year 2023 using the technique of multi-stage random sampling. The research instrument was a mathematical problem-solving diagnostic test on the greatest common divisor and least common multiple. Data analysis included finding the quality of the test and percentage. Findings are as follows, 1) The mathematical problem-solving diagnostic test was a six-item subjective test showing solutions. The test was used to diagnose students’ four steps of problem solving consisting of Step One: Problem analysis; Step Two: Planning problem solving and calculation methods to find solutions; Step Three: Problem solving; and Step Four: Checking answers. The quality of the mathematical problem-solving diagnostic test found to exhibit content validity of all items at 1.00; difficulty at 0.58-0.80; and discrimination at
0.62-0.87; the reliability of the whole test at 0.93. 2) The deficiencies in mathematical problem solving found that the highest proportion of students exhibited deficiencies in Step Four: Checking answers at the highest level. The students lacked understanding in the methods of determining the relationships between answers and checking answers.