The tree ammeter method and the three voltmeter method are used for measurements of power. More specifically, they are used to calculate the power factor of a specific load. Both methods are used on the Fundamentals of electrical engineering course in professional study of electrical engineering at the Zagreb University of Applied Sciences as an introduction to measurements of power and phasor arithmetic. Both methods are susceptible to accuracy problems caused by small errors in measuring devices. These accuracy problems in specific scenarios that were used during the course presented an opportunity to educate students on the difference of theory and its practical application. This paper examines our solution to the perceived accuracy problems and discusses the changes that were made in course material and teaching methods to highlight the difference between theory and practice.