the earth is approximately sphere with a radius of 6400 km. what is the volume of the earth?

radius of the earth is 6400. and also the formula is 4/3 pi r^3 to find the volume of the sphere.

so the volume of the earth is:

4/3 pi r^3

4/3 *22/7 *(6400)^3

=1098508190476.1904761904761904762

that is the answer

Go into Formulary at the top of this page.

Click on sphere

use the formula for volume  

radius of earth, r=6400km

Volume of earth = 4/3πr²
                        = $${\frac{{\mathtt{4}}}{{\mathtt{3}}}}{\mathtt{\,\times\,}}{\mathtt{3.14}}{\mathtt{\,\times\,}}{\mathtt{6\,400}}{\mathtt{\,\times\,}}{\mathtt{6\,400}} = {\mathtt{171\,485\,866.666\: \!666\: \!666\: \!666\: \!666\: \!7}}$$ km³

Not quite anonymous!  Volume of sphere is 

$$Volume = \frac{4}{3}\pi r^3$$

Note the r-cubed not squared.

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