A page is to contain 54 square centimeters of printed material. If the margins are 1 cm at the top and bottom and 0.5 cm at the sides, find the most economical width of the page (in cm).

Answer 1

w = width
54/w = height

The page area is thus

a = (w+1)(54/w + 2)

Assuming you want minimum page area,

da/dw = 0 at w = 3√3