Hamza is a smart fellow, he gets an A in a course 80% of the time. still, he likes his leisure, only studying for the final exam in half of the courses he takes. nevertheless, when he does study, he is almost sure (like 95%) to get an A.

Assuming get got an A, how likely is it he studied? if someone estimates the. above to be 75%, what error are they committing? Explain?