Question 359811
Since the diameter is 18 inches, the radius is {{{r=d/2=18/2=9}}} inches. So {{{r=9}}}



{{{V=pi*r^2*h}}} Start with the volume of a cylinder formula.



{{{V=pi*(9)^2(20)}}} Plug in {{{r=9}}} (the radius) and {{{h=20}}} (the height).



{{{V=(3.14159265)(9)^2(20)}}} Replace {{{pi}}} with {{{3.14159265}}} (note: Use more digits of {{{pi}}} to get better accuracy).



{{{V=(3.14159265)(81)(20))}}} Square {{{9}}} to get {{{81}}}.



{{{V=5089.380093}}} Multiply {{{3.14159265}}}, {{{81}}} and {{{20}}} to get {{{5089.380093}}} (this value is approximate).



{{{V=5089.38}}} Round to the nearest thousandth.



So the approximate volume is about 5089.38 cubic inches.



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