Question

What is the volume of a sphere with a radius of 7mm

Answer 1

1)  The answer, in terms of  "π", is:
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  "  ($\frac{1372 mm^3}{3}$) *  π    mm³ " .
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2) The answer, using "3.14" for "π", is:
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" 1436.0266666666666667  mm³ " ; round to: " 1436.027 mm³ " ; 

        or; write as: " 1436 $\frac{2}{75}$  mm³ " .
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Explanation: 
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The formula for the volume, "V" of a sphere is:

V = $\frac{4}{3}$ * π* r³ ;

in which "r" = radius = "7 mm" {given}.

We can solve using "3.14" for "π" ; or we can solve in terms of "π" ;
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1)  In terms of "π" :
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   V = $\frac{4}{3}$ * π * r³ ;

      = $\frac{4}{3}$ * π * (7 mm)³ ;

      = $\frac{4}{3}$ * π * (7 * 7 * 7 * mm³) ;
 
      = $\frac{4}{3}$ * π * (49 * 7 * mm³) ;

      = $\frac{4}{3}$ * π * (343 mm³) ;

      = $\frac{4* 343 mm^3}{3}$) * π   mm³

      =  ($\frac{1372 mm^3}{3}$) *  π    mm³  ;

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2)  Using "3.14" for "π" :
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     V = $\frac{4}{3}$ * π * r³ ; 

        = $\frac{4}{3}$ * (3.14)* (7 mm)³ ;

        = $\frac{4}{3}$ * (3.14) * (7 * 7 * 7 * mm³) ;

        = $\frac{4}{3}$ * (3.14) * (49 * 7 * mm³) ;

        = $\frac{4}{3}$ * (3.14) * (49 * 7 * mm³) ;

        = $\frac{4}{3}$ * (3.14)  * (343 mm³) ;

        = { $\frac{4}{3}$ }  * (3.14 * 343 mm³) ;

        = { $\frac{4}{3}$ } *  (1077.02 mm³) ;

        = (4 * 1077.02 mm³) / 3 ; 

        = (4308.08 mm³) / 3 ; 
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        =  1436.0266666666666667  mm³ ;  round to: " 1436.027 mm³ " ;

        or; write as: " 1436 $\frac{2}{75}$  mm³ " .
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