Jenna will drive 200 miles at a rate of 50 miles per hour, so she will drive for 4 hours.
Her friend will drive 100 miles at a rate of 20 miles per hour, so Jenna's friend will drive for 5 hours.
They will spend a total of 60 minutes on breaks because 30 minutes + 30 minutes = <<30+30=60>>60 minutes.
Thus, they will spend 1 hour on breaks because there are 60 minutes in an hour.
The road trip will take a total of 1+4+5 = <<1+4+5=10>>10 hours.
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