Tom was putting hardwood flooring into his living room that measured 16' long and 20' wide.  The flooring comes 10 sq ft per box and he has already put down 250 sq ft of flooring.  How many more boxes does Tom need to complete the job?
The entire sq ft of the living room is LxW so the room is 16x20 = <<16*20=320>>320 sq ft
Tom has already put down 250 sq ft so he needs to put down 320-250 = 70 sq ft of flooring
The boxes contain 10 sq ft of flooring per box and he needs 70 more sq ft of flooring so he needs 70/10 = <<70/10=7>>7 more boxes
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