Final answer:
The argument is invalid because it assumes a direct causation between studying hard and getting a good grade, ignoring other factors that can contribute to academic success.
Step-by-step explanation:
The argument “If I study hard, I will get a good grade. I did not study hard. Therefore, I will not get a good grade.” is an example of modus tollens, which is a valid form of argument in logical reasoning.
Modus tollens follows the structure: If P then Q; Not Q; Therefore, not P. However, in this specific case, the conclusion that one will not get a good grade does not logically follow from the premises because it assumes a direct and sole causation between studying hard and getting a good grade.
There could be other factors that contribute to getting a good grade, such as prior knowledge, test difficulty, or simply guessing correctly.
Therefore, based on critical thinking and understanding the nuances of student performance and the grading system, the argument is invalid. The outcome of not getting a good grade is not a direct consequence of the initial premise that studying hard leads to a good grade because one might achieve a good grade through other means regardless of the amount of study.