11,250
10,800 seconds.
Three hours.
12,600 seconds.
11,130 seconds.
8580 seconds
Three hours is 180 minutes, and 10800 seconds and 1/8 days.
12,300 seconds.
11250 (Search Google for "3 1/8 hours in seconds")
10,920 secs
3 minutes = 60 x 3 = 180 seconds one eighth of a minute = 60 ÷ 8 = 7.5 seconds 3 and one-eighth minutes = 187.5 seconds
Not sure if you want seconds in 3 and 1/2 hours or in three 1/2 hours. If it is the first case then 1 hour is 3600 seconds, hence 3 hours is 10800 seconds. Add to this the number of seconds in half hour which is 1800 to get a total of 12600 seconds If it is the second case then 1/2 hour is 1800 seconds, hence 3 half hours is 5400 seconds.
There are 24 times 7 times 3, or 504 hours in three weeks. Multiply by 60 to get minutes, 30240, and by 60 again to get seconds, 1814400.