HarveyKlaus wrote:

Hey All,

Its super basic but I'm having trouble in translating top/bottom/sides wording into length, width and height. As the general formula for the surface area of a cuboid/rectangular solid is 2(lw+wh+lh), how can we translate this into top/bottom/sides etc.?

Thanks!

The length, width and height changes according to the orientation of the box. The height right now is 5 inches but if you turn it 90 degrees, it could be 25 inches. But the overall surface area and volume stays the same irrespective of what you consider as length, breadth and height. Hence the formulas are symmetrical:

Surface Area = 2*(lb + bh + hl)

Volume = lbh

If you interchange l and b, the formula stays the same. So it doesn't really matter what you take as length breadth and height.

In this question, they have specified the orientation of the box and hence the face which is lying at the bottom. That face is the one which has area of 25*10.

Hence the surface area of the rest can be calculated as 2*(25*10 + 10*5 + 5*25) - 25*10

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