Question 204155
A rectangular solid and a circular cylinder have the same volume and the same height. The base of the rectangular solid is a square. Which (if any) of the following statements are true? 
(i) The rectangular solid and the cylinder have the same base area.
(ii) The rectangular solid has a greater base area than the cylinder.
(iii) The side length of the square base of the rectangular solid is equal to the diameter of the cylinder.
(iv) The side length of the square base of the rectangular solid is less than the diameter of the cylinder. 
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The volume of a solid that has a consistent cross-sectional area is that area times its height.
V = area*h
If the 2 volumes are equal, and the heights are the same, then the areas have to be equal.
That's (i).