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# Practical Question

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Hi good people,

(I am translating from an Afrikaans paper..) I have submitted a "Practical Problem" question as a guest, since for some reason I could not enable cookies and therefore could not log in. After I posted I tried again, and ..walla, I could suddenly log in..anyways, I have a second question of similar nature to the one I posted previously. Please help?...

a Man is making a garden, The garden is 120 square meters. The garden is to be rectangular. It's going to cost him R150 per square meter for the plant fencing which will run on three of the sides, and R250 per square meter for a wire mesh fence, which will run on the remaining side. The wire mesh fence will cover one of the long sides.

1) Write an expression for the width of the garden with relation to "x" if "x" is the length of the garden.

This one I got right...it is

$$A=lb$$

$$120=bx$$

$$b={120 \over x}$$

2) show that the costs, C, of the full fencing is: $$C=400x + 36000x^-1$$

just this one question please....thank you so much!

Apr 15, 2019

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There is a little error in the question here.

Hi Juriemagic,

A man is making a garden, The garden is 120 square meters. The garden is to be rectangular. It's going to cost him R150 per square meter for the plant fencing which will run on three of the sides, and R250 per square meter for a wire mesh fence, which will run on the remaining side. The wire mesh fence will cover one of the long sides.

The price is not per square metre becasue we are not given the height of the fence. It is just meant to be a price per metre.

You have already worked out that the dimenstions of the garden are   x and   120/x

x is the length so it has to be the long sides.

So on long side costs  R250 per metre so that is   R250x   (Rand is South African money)

Now the other 3 sides add up to (x  + 120/x  + 120/x) = ( x + 240/x )  and they cost R150 per metre.  So that is   R150( ( x + 240/x )

$$\text{Total cost }\\= 250x+ 150( ( x + 240/x ) \\=250x+150x+150*240x^{-1} \\= 400x+36000x^{-1}$$

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Apr 15, 2019
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I see, so that was the problem, the meter square...Melody, thank you very much..I really do appreciate...

juriemagic  Apr 15, 2019