Surface Area of a cylinder

[anusuthakaran]

When a question states '25 % of the surface area of a right circular cylinder is shaded'
do we consider the surface area:

.25 ( pi.r^2h + 2pi.r^2) or

.25 (pi.r^2h)

i.e., when no information or description is provided regarding the number of surfaces of a cylinder, do we consider it a closed figure or an open ended figure ?

Regards,
Anu.

[esledge]

Always consider a cylinder a closed figure (Full area = 2h*pi*r+2pi*r^2. Note: your formula had a typo.)

The open-ended figure is a tube, not a cylinder :-) (Surface area of the outside of a tube = 2h*pi*r, but that's just for fun; I don't think the GMAT ever describes such a figure.)