quick help (1 Viewer)

chewy123

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A manufacturer wishes to make a can, which is to be in the shape of a circular cylinder, that holds 1 litre. Find the dimensions of the cylinder with the condition that the area of metal required to form the can is to be a minimum if the can is to be closed.

For me: Please show standard working out for these kinds of question.

Thanks all.
 

12o9

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can someone check the asnwers? my answers seem dodge.
 

chewy123

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I tried the same method as yours but not could get it.

Answer is r=5.42cm h=10.8cm
but I dunno how to get it ><
 
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lyounamu

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1 litre = 1000cm^3

Let's work it out from there.

So you get the answers as what OP suggsted.

So 4pi . r^3 = 2000
r^3 = 159.1549431...
r = 5.41926070....

And susbstitute that back in to find h.

1000 = pi . r^2 . h
h = 1000/(pi . r^2)
= 10.838521...
 
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12o9

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lyounamu said:
1 litre = 1000cm^3

Let's work it out from there.

So you get the answers as what OP suggsted.
oh crap. i forgot about that x).
 

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