Question

What is the approximate volume of the pyramid?

Answer 1

Just multiply all of the numbers and you will get 1472 ft3

Answer 2

The correct answer is:  [C]:  " 491 ft³ " .
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Explanation:
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Note the formula/equation for the volume of a pyramid: 

Volume of a pyramid, "V" :  

V  =  (⅓) *(base area) *
    (perpendicular height; that is height measured from center of base to                                                                                                                apex) ; 
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  base area (which is a square, in this case)  =
                            length * width  =   8 ft * 8 ft  =  64 ft ² ; 
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  perpendicular height  =  23 ft ;
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V = (⅓) * (64 ft ²) * (23 ft) ; 

=  [(64 ft ²) *(23 ft)] / 3 = 1472 ft³ / 3 ;

= 490. 66666...  ft³ ; (that is; "490 ⅔  ft³ ") ;  which is closest to (rounds up to):

Answer choice:  [C]:  491 ft³  .
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