The Surface area of smaller cube = 294 square centimetres = 6*L*L where L is the length of the side of the cube solving for which L = 7
The Surface area of smaller cube = 2646 square centimetres = 6*L1*L1 where L1 is the length of the side of the cube solving for which L1 = 21

Now to calculate how many smaller squares can be carved out from the bigger cube, one simply needs to divide the volume of the bigger cube by the smaller one
Vol of the big cube = 21^3 = (7^3)*(3^3) = a
The volume of small cuber = (7^3) = b
# cubes that can be formed out = a/b = 3^3 = 27

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