The baby sleeps 20 hours a day because 2.5 x 8 = <<2.5*8=20>>20
The baby sleeps 2 times as much as the father because 60 / 30 = <<60/30=2>>2
The father sleeps 10 hours a night because 20 / 2 = <<20/2=10>>10
The father sleeps for 70 hours a week because 7 x 10 = <<7*10=70>>70
#### 70