SOLUTION: please help me solve this. tennis balls are packed into a square box 12 inches on one side. The tennis balls can be touching but can not be compressed. I divided 12 by 2.5(the dia

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Question 984969: please help me solve this.
tennis balls are packed into a square box 12 inches on one side. The tennis balls can be touching but can not be compressed. I divided 12 by 2.5(the diameter of the tennis balls) and that equals 4.8. I rounded 4.8 up to the nearest whole number(5) and multiplied 5x5x5 and got 125 tennis balls... after that I'm lost. The remaining space in the box is filled with packing beads, I am supposed to find the volume occupied by packing beads and also the percentage of the volume the box is filled with beads.

Answer by vleith(2983) (Show Source):
You can put this solution on YOUR website!
The problem stats you cannot compress the balls; so you can not round up. You must round down. That means 4 x4 x4. There will be 16 balls per layer and 4 layers. So 48 balls.

The volume of the box is inches.
You are told the diameter of a ball is 2.5 inches. So the radius of a ball is 1.25 inches
The volume of each ball is
Subtract the volume of 16 balls from the volume of the box to get the volume of the packing bead material
To get the percentage of beads to box, divide the bead volume by the box volume and multiply by 100%