Answer: 10 hours, 20 minutes
This is equivalent to 620 minutes.
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Step-by-step explanation:
The user purrugh has a great answer. I'll provide a slightly different approach.
The timespan from 8:25 PM to 9:00 PM is 35 minutes. Note how adding 35 minutes to 25 past the hour gets us to 25+35 = 60 minutes, so we're at the top of the hour now, and at 9 o' clock on the dot.
Then from 9 PM to 12 midnight is a gap of 3 hours (because 12-9 = 3). From midnight to 6 AM is another 6 hours. So far we have 3+6 = 9 hours, plus the additional 35 minutes mentioned earlier. The duration so far is 9 hours, 35 minutes. We still have to account for another 45 minutes, since we want to get to 6:45 AM and not 6:00 AM.
Note how 35+45 = 80, which is over 60. This means 35 min + 45 min = 80 min = (60 min) + (20 min) = 1 hr, 20 min
That "1 hr, 20 min" is added onto the "9 hours" from earlier and we arrive at 10 hours, 20 minutes as the final answer
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Yet another approach is to do everything in minutes, and then convert to hours,minutes format at the very end.
Again the gap from 8:25 PM to 9:00 PM is 35 minutes. From 9 PM to midnight is 3 hours, or 3*60 = 180 minutes. We have a duration so far of 35+180 = 215 minutes.
From midnight to 6 AM is 6*60 = 360 minutes. The duration has been updated to 360+215 = 575 minutes. Finally, from 6 AM to 6:45 AM is the last gap of 45 min to get us to 575+45 = 620 minutes.
Tucker slept a total of 620 minutes. Let's convert that to hours,minutes format. Note how 620 = 600+20 and how 600/60 = 10. Meaning that 600 minutes = 10 hours. Therefore,
620 min = (600 min) + (20 min) = 10 hours, 20 minutes