Each 5 by 5 painting is 25 square feet because 5 x 5 = <<5*5=25>>25
All three of them take up 75 square feet because 3 x 25 = <<3*25=75>>75
The 10 by 8 painting takes up 80 square feet because 10 x 8 = <<10*8=80>>80
These four paintings take up 155 square feet because 80 + 75 = <<80+75=155>>155
The final painting is 45 square feet because 200-155 = <<200-155=45>>45
If it is 5 feet wide it is 9 feet tall because 45 / 5 = 9
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