Mitch, not trying to be difficult. Just saying how it works. You have to know the current draw of the load, not the source. I bet if you shorted out one AAA battery it could supply over 1 amp (same for 4 in series BTW). If you have a meter with a 10 amp current range you could do this yourself. Simply put the probes across the battery. Your fan likely draws less than 200 ma.
Pete