The Total solution for NCERT class 6-12
Given,
Radius of metallicsphere = R = 10.5 cm
So, its volume = 4/3πR3 = 4/3 π(10.5)3
We also have,
Radius of each cone =r = 3.5 cm
Height of each cone =h = 3 cm
And, its volume = 1/3πr2h = 1/3 π(3.5)2(3)
Thus,
The number of cones =Volume of metallic sphere/ Volume of each cone
= 4/3 π(10.5)3 /1/3 π(3.5)2(3)
= 126