Q6 of 76 Page 18

Three equal cubes are placed adjacently in a row. Find the ratio to total surface area on the new cuboid to that of the sum of the surface areas of the three cubes.

Given,


Let length of an edge of three equal cubes = a


Total surface area of 3 cubes = 3× 6a2 = 18a2


(While putting these cubes in a row adjacently, a cuboid is formed)


∴ length of cuboid = 3a


Breadth of cuboid = a


Height of cuboid = a


So,


total surface area of cuboid = 2(3a2+a2+3a2) = 14 a2


Hence,


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