SOLUTION: what is the total surface area of a cube when it's edge is doubled,tripled & halved

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Question 122283: what is the total surface area of a cube when it's edge is doubled,tripled & halved
Answer by psbhowmick(878) About Me  (Show Source):
You can put this solution on YOUR website!
The total surface area of a cube with edge 'a' is given by
S+=+6a%5E2.
If edge is doubled, then the edge '2a' in the above formula and so the new total surface area is
S%5Bnew%5D+=+6%282a%29%5E2+=+4x%286a%5E2%29+=+4S i.e. 4 times original total surface area.
If edge is trebled, then the edge '3a' in the above formula and so the new total surface area is
S%5Bnew%5D+=+6%283a%29%5E2+=+9x%286a%5E2%29+=+9S i.e. 9 times original total surface area.
If edge is halved, then the edge a%2F2 in the above formula and so the new total surface area is
S%5Bnew%5D+=+6%28a%2F2%29%5E2+=+%286a%5E2%29%2F4+=+S%2F4 i.e. one-fourth original total surface area.