Multiple choice

If a solid metallic sphere of radius $8$ cm is melted and recasted into $n$ spherical solid balls of radius $1$ cm, then $n$ is:

  1. $500$
  2. $510$
  3. $512$
  4. $516$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Volume of large sphere = (4/3) * pi * 8^3. Volume of small sphere = (4/3) * pi * 1^3. Number of balls n = (8^3) / (1^3) = 512.

AI explanation

Because the volume remains unchanged when the metallic sphere is melted and recast, the volume of the large sphere equals the total volume of the n small balls. Using the sphere volume formula, four thirds times pi times 8 cubed equals n times four thirds times pi times 1 cubed. Solving for n gives n equals 8 cubed, which results in 512.