Solution:Let the number of cube that can be formed by melting a 15 cm cube of metal be .
Now, let’s find the value of the cube of sides 3 cm first.
Volume of 3 cm cube
So, to calculate the volume of n number of cubes of sides 3 cm, we will multiply it with n.
Volume of number of 3 cm cube
Now, volume of cube of sides 15 cm
Now, equating equation (1) with equation (2) we get;
So, the number of 3 cm cubes that can be formed by melting a 15 cm cube of metal is 125.