Question
If the radius of a right circular cylinder is tripled and its altitude is cut in half, then the ratio of the volume of the original cylinder to the volume of the altered cylinder is?
Answers
Reiny
original radius and height : r and h
volume = π r^2 h
new radius = 3r
new height = h/2
new volume = π (3r)^2 (h/2)
= (9/2) π r^2 h
ratio of old volume to new volume
= πr^2 h : (9/2) π r^2 h
= 1 : 9/2
= 2 : 9
volume = π r^2 h
new radius = 3r
new height = h/2
new volume = π (3r)^2 (h/2)
= (9/2) π r^2 h
ratio of old volume to new volume
= πr^2 h : (9/2) π r^2 h
= 1 : 9/2
= 2 : 9
sef ds
dsaf