Q13 of 77 Page 21

Three cubes whose edges measure 3 cm, 4 cm, and 5 cm respectively are melted to form a new cube. Find the surface area of the new cube formed.

Given,


Edge of three cubes are respectively = 3cm , 4 cm , 5 cm


So,


Sum of volume of these cubes =


After melted these cubes a new cube is formed.


Let edge length of this new cube = a cm


So,


=


=


Edge of new cube = 6 cm


Surface area of new cube =


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