Forty-eight subjects from a university general psychology class took a series of four timed arithmetic tests of two differing complexities. Vocal music was played during half of the tests while instrumental music was played during the other half. Results were analyzed for the number of problems correct, number attempted and percentage of problems answered correctly. Results showed that subjects in the instrumental music condition had a significantly higher number of problems correct and attempted than the vocal condition, but the percentage correct was not significantly higher. Results for task complexity showed difficult problems had a significantly lower number correct and attempted and also a significantly lower percentage correct than easy problems had. An analysis of the interaction between music condition and task complexity was not significant
