Final answer:
George can build 1/3 of a fence section per hour. This relates to the mathematical concept of rates.
Step-by-step explanation:
George is building a fence at a constant rate of 1/3 section per hour. Therefore, George can build 1/3 of a section of the fence each hour. This information is related to the field of Mathematics, specifically to the topic of rates and proportions, which are often covered in High School math curricula.