Word problem-I would like to check my procedure

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word problem-Please help me to check my procedure

Homework Statement



A cubical ice block is melting at a rate that relates to its surface area. Set up an equation for the volume of a cube, C, in terms of its surface area, S.

Homework Equations



C=x^3
S=6x^2

The Attempt at a Solution




let length of the side of the cube:x
dC/dx=3x^2 dS/dx=12x dC/dS=x/4
Now what should I do? I think I did pretty well until now. How should I use this information for getting the answer? Or dC/dS(which is x/4) is the final answer?
 
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Thank you. But work with S? Would you mind if I want more specific explanation from you? Sorry, cause I am not very good at math, interpreting word problems.
 
The problem said "Set up an equation for the volume of a cube, C, in terms of its surface area, S". That's why you need to "work with S".
You have [itex]C= x^3[/itex]. You also know that [/itex]S= 6x^2[/itex].

Solve [itex]S= 6x^2[/itex] for x (which is a length and so positive) and replace the "x" in [itex]C= x^3[/itex] with that/