His first TV was 384 square inches because 24 x 16 = <<24*16=384>>384
His first TV cost $1.75 per square inch because 672 / 384 = <<672/384=1.75>>1.75
His new TV is 1,536 square inches.
It costs $.5 per square inch because 1152/ 1,536 = .5
His old TV cost $1 more per square inch because 1.75 - .75 = <<1.75-.75=1>>1
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