Adele and Kent will not have the same amount in their account at the same time. because they both are going at the same rate depositing 45$a month Adele is ahead by 30$ because she deposited 100 instead of 70 in the beginning. They will be at the same point if Kent deposits more or Adele deposit less.
The volume of the first floor is 9000 inches cubed. 20*45*10=9000 The volume of the attic is 360 inches cubed. 8*45=360 You don't have to divide by two as there are two triangular prisms.
