In quantitative research methods, the systematic investigation of observable relationships is primarily concerned with ________ using mathematical and statistical techniques.

In quantitative research methods, the systematic investigation of observable relationships is primarily concerned with measuring and analyzing data using mathematical and statistical techniques. This means researchers collect numerical information to find patterns or test theories about how different things relate to each other. For example, if a researcher wants to know if studying more hours leads to better exam scores, they would gather data on study hours and exam results from many students. By applying statistical methods, they can determine if there is a significant relationship between the two variables. This approach helps to provide clear, objective evidence that can support or challenge existing ideas.