Each student's effort is an important factor in achievement. Mathematics is an important subject for business students since there is a strong connection between performance in mathematics and success in business courses. The purpose of this paper is to identify the factors influencing a student's choice of how much effort to put into studying business mathematics by questioning 273 students from two business schools in Norway. There is a considerable variation in the study time. By using a linear regression model, we identify the variables linked to effort. Females, and those who have higher enjoyment of mathematics, exert higher effort in business mathematics. Those with a strong background in mathematics from high school and students with parents who have higher education exert less effort in business mathematics. The attitudes toward mathematics do not seem to considerably affect effort.