(Assuming the paper goes around the side of the tin only and not the top/bottom)
Imagine the net of this can. It is a cylinder, so it would consist of a rectangle and two circles, the surface area of this rectangle is what we're being asked for.
The length and width of the rectangle are needed to find the area, (area of a rectangle=length*width). The width is marked as 3in. The length is equal to the circumference of the circle (with radius 2in):
