Question 1009282
There are two tvs of different sizes. One is a 42" diagonal TV that costs $420, the other is a 50" diagonal tv that costs $550. The aspect ratio of each is 16:9, width to height. What is the cost per square inch of each tv? 
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Note:: 16:9 is the same as 16x:9x
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Equation for 42" TV::
sqrt[(16x)^2+(9x)^2] = 42
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(16x)^2 + (9x)^2 = 42^2
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337x^2 = 1764
x^2 = 5.2344
x = 2.287
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Dimensions::
9x = 20.59"
16x = 29.73"
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Area = 612.16 sq in
Cost per square in:: $420/612.16 = $0.69
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I'll leave the 2nd TV cost per square in to you.
Cheers,
Stan H.
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