.25 hours is equal to 15 minutes. This is calculated by multiplying .25 by 60, since there are 60 minutes in an hour. Thus, .25 hours represents a quarter of an hour.
25hours total
2hours... 120mins.. .25hours =15min.. 2hours .25min = 120+15=135
Originally they were tape, however modern FDR's use solid state technology to record unto 25hours of data.
1525/60 = 25 hours (and a bit) 1525 - (25 * 60) = 25 minutes Therefore the answer is 25hours and 25 minutes.