Step-by-step explanation:
Radius of first sphere is 30 cm.
Volume of first sphere is :
[tex]V_1=\dfrac{4}{3}\pi r_1^3\\\\V_1=\dfrac{4}{3}\times 3.14\times (30)^3\\\\V_1=113040\ cm^3[/tex]
Radius of second sphere is 60 cm.
Volume of second sphere is :
[tex]V_2=\dfrac{4}{3}\pi r_2^3\\\\V_2=\dfrac{4}{3}\times 3.14\times (60)^3\\\\V_2=904320\ cm^3[/tex]
Dividing volume of second sphere to that of volume of first sphere. So
[tex]\dfrac{V_2}{V_1}=\dfrac{904320}{113040}\\\\\dfrac{V_2}{V_1}=8\\\\V_2=8V_1[/tex]
So, the volume of the larger sphere is 8 times of the volume of smaller sphere.