Q13 of 76 Page 18

A metal cube of edge 12 cm is melted and formed into three smaller cubes. If the edges of the two smaller cubes are 6 cm and 8 cm, find the edge of the third smaller cube.

Given,


Edge of metal cube = 12 cm


Volume of cube = a3 = 123 = 1728 cm3


Edge of 2 smaller cube = 6cm , 8 cm


Let edge of 3rd cube = x cm


So, 63+83+ x3 = 1728


= x3 = 1728 – (216+512) = 1000


= x =


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