document.write( "Question 53409: Good evening, i would like to ask you this three problems, i am not sure that i work out the answers. Please, help in those
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document.write( "1) A solid cube of side 6 is first painted pink and then cut into smaller cubes of side 2. How many of the smaller cubes have paint on exactly 2 sides?\r
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document.write( "2) A regular hexagon is inscribed in a circle o radius R cms. What is the perimeter of the regular hexagon?\r
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document.write( "3) A 4cm cube is cut into 1cm cubes. What is the percentage increase in the surface area after such cutting?\r
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document.write( " From yours poor students
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document.write( " babynarah and modi \n" );
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Algebra.Com's Answer #35700 by stanbon(75887)![]() ![]() ![]() You can put this solution on YOUR website! 1) A solid cube of side 6 is first painted pink and then cut into smaller cubes of side 2. How many of the smaller cubes have paint on exactly 2 sides? \n" ); document.write( "Before cutting the cube is 6^3 cb. units = 216 cu units \n" ); document.write( "The smaller cubes are 2^3 units or 8 cu units \n" ); document.write( "Dividing 216 by 8 you get 27 small cubes. \n" ); document.write( "How many of them have paint on exactly two sides? \n" ); document.write( "There are four on each edge; so there are 4*6=24 with exactly \n" ); document.write( "two pink sides. \n" ); document.write( "------------- \n" ); document.write( "2) A regular hexagon is inscribed in a circle of radius R cms. What is the perimeter of the regular hexagon? \n" ); document.write( "Draw the picture of the hexagon. \n" ); document.write( "Draw the 6 radii--one to each of the six vertices. \n" ); document.write( "Each of the triangles formed is an equilateral triangle. \n" ); document.write( "So all sides of each triagle are length 6. \n" ); document.write( "So the perimeter of the hexagon is 6*6= 36 cm\r \n" ); document.write( "\n" ); document.write( "3) A 4cm cube is cut into 1cm cubes. What is the percentage increase in the surface area after such cutting? \n" ); document.write( "The surface area of the original cube is 6*4^2=96 cm sq. \n" ); document.write( "Each of the 1cm cubes has a surface area of 6*1^2=6 cm sq. \n" ); document.write( "There are 4^3=64 small cubes \n" ); document.write( "The total surface area of the small cubes is 64*6=384 cm sq. \n" ); document.write( "The increase in surface area is 384-96= 288 sq cm. \n" ); document.write( "The % increase in surface area is 288/96=300% \n" ); document.write( "Cheers, \n" ); document.write( "Stan H. \n" ); document.write( " \n" ); document.write( " |