The correct answer is: [C]: " 491 ft³ " . _______________________________________________ Explanation: _______________________________________________ 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) ; _______________________________________________________ base area (which is a square, in this case) = length * width = 8 ft * 8 ft = 64 ft ² ; _______________________________________________________ perpendicular height = 23 ft ; _______________________________________________________
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):
48 girls are there. Given that there is a ratio of boys to girls of 7:8. Then divide 42 boys by 7 boys which equals 6. After, multiply 6 by 8 girls equals 48 girls.
