A metallic sphere of radius 12 cm is melted into three smaller spheres. If the radii of two smaller spheres are 6 cm and 8 cm, the radius of the third is?
Correct Answer: 10 cm
Explanation:
Let radius of the third sphere be r.
Then, 4/3 π x (12)3 = 4/3 π x (6)3 + 4/3π x (8)3 + 4/3 πr3
⇒ (12)3 = (6)3 + (8)3 + r3
⇒ r3 = 1728 - 216 - 512
⇒ r3 = 1000
∴ r = 10 cm
