We use Markov chain Monte Carlo (MCMC) analysis to construct a three-question math quiz to assess key skills needed for introductory finance. We begin with data collected from a ten-question criterion-referenced math quiz given to 314 undergraduates on the first day of class. MCMC indicates the top three questions for predicting overall course performance. This brief assessment explains approximately 10% of the variance in undergraduate introductory course performance. The quiz holds potential within the classroom for students, instructors, and university administration to better identify math skill deficiencies relevant to finance.