Oilers/Plant Tenders (HHC) Civil Service Practice Exam 2026 - Free Oilers & Plant Tenders Practice Questions and Study Guide

When an oil drum is described as being 5/8 empty, it indicates that 5/8 of its total capacity does not contain oil. To determine how full the drum is, one must recognize that the entirety of the drum is represented as 1, or 8/8 when expressing it in eighths.

Thus, if 5/8 of the drum is empty, the portion that is full can be calculated by subtracting the empty portion from the whole. This involves taking 8/8 (the full capacity) and subtracting 5/8 (the empty part):

8/8 - 5/8 = 3/8.

Therefore, the fraction that represents how full the oil drum is would be 3/8. This is why the answer indicating that the drum is 3/8 full is correct.