This research aims to find out the effect of the application of realistic mathematics education on the achievement of learning mathematics by kovariabel numerical ability in students of the Bogor Unity Informatics Institute of Strata Management Prodi one this study uses the archetype of The Posttest Only Control Group with numerical ability kovariabel. Data collection techniques use interviews and questionnaires, while sampling techniques use non probability sampling with a sample count of 90 people. The results showed that the application of realstic mathematics education and conventional learning had a positive and significant effect on student learning achievement through student numerical abilities. This is seen from the results of simple linear regression analysis, multiple linear regression, t test, determination coefficient test, sobel test and line analysis. Numerical ability as a moderator variable mediates between the application of realstic mathematics education to student learning achievement which is partial mediation and numerical ability as a moderator variable that mediates between the application of student realstic mathematics education to student learning achievement which is both full mediation.

Keywords : Conventional Learning, Learning Motivation, Numerical Ability, Student Learning Achievement.