Paul has 10 hours of homework from weekdays because 2 x 5 = <<10=10>>10
He has 15 total hours because 5 + 10 = <<5+10=15>>15
He has 5 days to do his homework because 7 - 2 = <<7-2=5>>5
He needs to do 3 hours a night because 15 / 5 = <<15/5=3>>3
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