According to the information found in the search results, a 78 percent grade falls under the C+ grade category. It is not considered a failing grade, as only an F grade is considered a failing grade. The GPA equivalent of a 78 percent grade is 2.3. However, it is important to note that grading systems can vary between schools and countries, so it is always best to check with your specific institution to understand how grades are calculated and what they mean.