Question 1015291:  a long of wood dimension 2m×20cm×10cm is cut on small blocks of 10cm×5cm×4cm how many blocks will be get? what will be the total surface area of all these blocks ? ans 
 Answer by FrankM(1040)      (Show Source): 
You can  put this solution on YOUR website! 2m×20cm×10cm is cut on small blocks of 10cm×5cm×4cm
 
2m=200cm, so it's really
 
200cm×20cm×10cm is cut on small blocks of 10cm×5cm×4cm
 
The first block has a volume of 40,000 cubic cm. 
The second block has a volume of 200 cubic cm.
 
The first block contains volume equal to 200 of the second.
 
The second sized blocks have 6 faces 2*((10*5)+10*4)+(4*5)) = 210 sq cm (you see, a rectangular solid has 2 of each of the 3 sized faces, so 3 multiplies, then times 2)
 
210 sq cm each times 200 blocks is 42,000 sq cm. 
 
(thank you for reading my note and reposting) 
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