Here is how I determined this mentally... There are 12 hours from 8:00am to 8:00pm ... so there is 1/2-hour less for the hours of 8:30am to 8:00pm ... which means 11 and 1/2 (11.5) hours.
There are 8.5 hours. * hours and 30 minutes
Eight hours and thirty minutes.
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8:00am is eight hours, 8:00pm is twenty hours (20:00). 12:00am is zero hours (00:00), 12:00pm is twelve hours. 12:30am is thirty minutes (00:30), 12:30pm is twelve hours and thirty minutes. 4:30am is four hours and thirty minutes, 4:30pm is sixteen hours and thirty minutes (16:30).
The total hours from 8 am to 3:30 pm is 7.5 hours.
0:26 + 2:00 + 11:12 = 13:38 thirteen hours thirty-eight minutes
Four hours and thirty minutes.
Five hours and thirty minutes.
Thirty seconds is one half minute. Four minutes is the product of eight half minutes (8/2=4).
There are 19,800 seconds in five hours and thirty minutes. You need to do the math. All you need to do is multiply.
Five hours thirty minutes
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