On Mingming's birthday, my father bought a cake. The height of the cake box is 20cm, and the ribbon of the box is 2.3m long. How many square meters does it take to make this cake box?

Ribbon 2.3m = 230cm

230-30=200cm is a cake box? 4* height +2* length +2* width,? 4* height +2* box diameter =200cm

2(2* height+box diameter) =200cm

? 2* height+box diameter = 100cm

? Because the height is 20cm, 2*20+ box diameter = 100cm.

? 40+ box diameter = 100cm

Box diameter =60cm.

So the radius of the box is 60/2=30cm.

So the two circular areas of the cake box are 2πr? =2*π*30*30= 1800π? (cm？ )

The side area of the cake box is the bottom perimeter * height = 2π r * h = 2 * π * 30 * 20 =1200π (cm? )

So the cake box needs1800π+1200π = 3000π (cm? )

None of the above.

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Actually, I think there is something wrong with your topic. It's a little unclear. First, there are both cylindrical and rectangular cake boxes, so there are two solutions to this problem; Second? Because I don't know what age you are studying now, every grade will have different answers, so I will help you answer them in detail, for fear that this is not your knowledge! ~

Scheme 1: cylindrical cake box with round bottom.