Question

A cylinder with radius 3 meters and height 7 meters has its radius doubled. How many times greater is the volume of the larger cylinder than the smaller​ cylinder?

Answer 1

V1 = old volume
V1 = pi*r^2*h
V1 = pi*3^2*7
V1 = 63pi

V2 = new volume (with radius doubled)
V2 = pi*r^2*h
V2 = pi*6^2*7
V2 = 252pi

Divide the two volumes
V2/V1 = 252pi/63pi = 252/63 = 4

Answer: 4
The larger volume is 4 times greater than the smaller volume.