First find the area of one of the long walls: 30 feet * 12 feet = <<30*12=360>>360 square feet

Then double that amount since there are two walls: 360 square feet * 2 = <<360*2=720>>720 square feet

Then find the area of the short wall: 20 feet * 12 feet = <<20*12=240>>240 square feet

Then add that area to the area of the two long walls to find the total area: 720 square feet + 240 square feet = <<720+240=960>>960 square feet

# Answer

960
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
James is building a hall of mirrors. Three of the walls will be completed covered with glass. If two of those walls are 30 feet by 12 feet and the third is 20 feet by 12 feet, how many square feet of glass does he need?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
960
James is building a hall of mirrors. Three of the walls will be completed covered with glass. If two of those walls are 30 feet by 12 feet and the third is 20 feet by 12 feet, how many square feet of glass does he need?
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