Across Monday through Friday, the total number of hours Harry sleeps is 8 + 7 + 8 + 10 + 7 = <<8+7+8+10+7=40>>40 hours
The total number of days from Monday through Friday is <<5=5>>5 days
The average number of hours Harry sleeps in one night is 40 / 5 = <<40/5=8>>8 hours
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