Question 900473
Density would help.
The forty pound bag delivers a volume of {{{10(1/12)=5/6}}} cubic feet of soil.
You can use the density as {{{40/(5/6)=240/5=highlight_green(48)}}} pounds per cubic foot.


The description for the question part is missing a word, believed to be "cubic".
You must mean, how many bags to fill 200 CUBIC meters by 4 centimeters.  You must do some
unit conversions.


{{{200*(0.04)*m^3*100*100*100*(cm^3/m^3)*(1/2.54)^3*(inch/cm)^3*(1/12)^3*(feet/inch)^3}}}
{{{highlight_green((200*0.04*10^6)/((2.54)^3*12^3))}}}   {{{highlight_green(feet^3)}}}


What you really need to use now is just this:


That is 282.5 cubic feet, allowing for four significant figures (probably more than justifiable).


Again, 1 bag of topsoil is {{{5/6}}} cubic feet.  How many {{{5/6}}} cubic feet contained in 282.5 cubic feet?
That is how many bags of the topsoil.
{{{282.5/(5/6)}}}
{{{6(282.5)/5}}}
{{{highlight(339)}}} bags



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When you know the part of the question that is missing, you should be able to make the needed changes in the solution process.