Community college leaders have spent years trying to improve success rates for students in developmental mathematics (DM) courses, but with little progress. This quantitative study, using a pre-experimental static-group research design, examined if a change in a community college district's policy and practices for student placement into DM courses could improve student success in online DM courses. Bounded rationality theory provided the lens to view how students' decision making is influenced by the lack of timely and appropriate information during the placement process. The study addressed whether a composite placement score, the result of combining the ACCUPLACER placement scores for elementary algebra and reading comprehension, would improve predicting student success in the online DM courses of basic arithmetic and introductory algebra. Logistic regression was used to analyze archival data from a student population of 39,585 students from which 767 participants were identified using a stratified random sampling method. The findings indicated that the composite score was a statistically significant predictor of the likelihood of student success only for the online basic arithmetic course (beta = 0.024, Exp(beta) = 1.024, p < 0.0005), which means the higher the composite placement score, the greater the likelihood of success. Providing DM students with information on reading proficiency's influence can increase student success rates. The social change implications are that when students are placed properly in a DM course they complete the sequence in less time, reach their academic goals sooner, and spend less money. In turn, the community college and local community also benefit. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]