In the international system of units, the second is the base unit of time. Convert any time Value to Seconds Using Multiplication. Example:- Convert 120 minutes into Seconds Multiply 120 minutes by 60 seconds per minute 120 min*60s/min=7200 seconds example: convert 28,800 seconds into hours Multiply 28,800 seconds by 12 hours per day 12 hours*12 hours per day = 3,732 hours Minute converter definition:- -A period of time equal to sixty seconds or 1/60th of an hour. 120 minutes equals 2 hours because 120/60=2. You can convert minutes to hours by dividing the number of minutes by 60. Hour converter definition:- - An hour is a period of sixty minutes. Divided into 60 minutes, it is the twenty-fourth part of a day and night. As there are 60 minutes in an hours, that’s the ratio used in the formula to convert 90 minutes to hours. 90 min = (90 ÷ 60) = 1.5 hr.