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Three-dimensional problems in fifth grade mathematics
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1 The total volume of the layer is 1*2/2= 1.

The total volume of the second layer is 1*2/2+2*3/2=4.

The total volume of the three layers is1* 2/2+2 * 3/2+3 * 4/2 =10.

The total volume of the four floors is1* 2/2+2 * 3/2+3 * 4/2+4 * 5/2 = 20.

The total volume of layer N is1* 2/2+2 * 3/2+3 * 4/2+...+n * (n+1)/2 = n * (n+1) * (n+2)/6.

Total volume of 8 floors =8*9* 10/6= 120.

superficial area

The total surface area of layer 1 is 1*6=6.

The total surface area of layer 2 is (1+2)*6= 18.

The total surface area of the three layers is (1+2+3)*6=36.

The total surface area of the four layers is (1+2+3+4)*6=60.

The total surface area of N layer is (1+2+3+4+) ...+n) * 6 = n * (n+1) * 3.

The total surface area of 8 layers is 8*9*3=2 16.