Answer:
He would be done by 10:30
Step-by-step explanation:
If you have 6:30 and you add 4 hours to it you end up with 10:30 because, forget the '30' for a second and take 6:00. You go 6 to 7 = 1 hour. 7 to 8 = 2 hours. 8 to 9 = 3 hours. 9 to 10 equals 4 hours. Which is what we are trying to get to. So you take that 10 and add the '30 back to it and you get 10:30.
Hope this helps you :)
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