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 Nov 4, 2017

Best Answer 

 #1
avatar+7350 
+1

surface area of cylinder  =  (circumference of base)(height) + 2(area of base)

 

surface area of cylinder  =  2 pi r h  +  2 pi r2               r  =  60/2  =  30    and    h = 4 * 60  =  240

 

surface area of cylinder  =  2 pi (30)(240)  +  2 pi (30)2

 

surface area of cylinder  =  14400pi + 1800pi   =   16200pi   ≈   50894 square mm

 

 

surface area of box  =  2LW + 2LH + 2HW

 

And  L = 60 + 60 = 120 mm ,  W = 60 + 60 = 120 mm ,  H = 60 mm

 

surface area of box  =  2(120)(120) + 2(120)(60) + 2(60)(120)

 

surface area of box  =  28800 + 14400 + 14400   =   57600 square mm

 

 

50894  is less than  57600 , so the cylinder has a smaller surface area.

 Nov 4, 2017
edited by hectictar  Nov 5, 2017
 #1
avatar+7350 
+1
Best Answer

surface area of cylinder  =  (circumference of base)(height) + 2(area of base)

 

surface area of cylinder  =  2 pi r h  +  2 pi r2               r  =  60/2  =  30    and    h = 4 * 60  =  240

 

surface area of cylinder  =  2 pi (30)(240)  +  2 pi (30)2

 

surface area of cylinder  =  14400pi + 1800pi   =   16200pi   ≈   50894 square mm

 

 

surface area of box  =  2LW + 2LH + 2HW

 

And  L = 60 + 60 = 120 mm ,  W = 60 + 60 = 120 mm ,  H = 60 mm

 

surface area of box  =  2(120)(120) + 2(120)(60) + 2(60)(120)

 

surface area of box  =  28800 + 14400 + 14400   =   57600 square mm

 

 

50894  is less than  57600 , so the cylinder has a smaller surface area.

hectictar Nov 4, 2017
edited by hectictar  Nov 5, 2017

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