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Ganesh Ujwal April 28th, 2018 10:00 PM

Please explain the solution.
 
A Cube is decorated in such a way that one diamond is placed at each corner, 6 diamonds are placed at each edges and 3 diamonds are placed at the center of each face. How many diamonds are there on the cube?

Solution: No of units = (E - 2C) 12

Corner = 8 X 1 = 8

Edges = (E-2C) 12 = (5 - 2X1)8 = 36

Face = 6 x 3 = 18.

My friend showed me a solution to this problem and hesitate to explain it. please help me.

skipjack April 28th, 2018 11:02 PM

There are inconsistencies. The description states that 6 diamonds are placed on each edge, but the solution uses E = 5. Also, the solution incorrectly changes 12 (the number of edges) to 8.

In the description, it's unclear whether the number of diamonds placed on each edge includes the diamonds at the ends of each edge (the corner diamonds).

If the 6 diamonds placed on each edge include 2 corner diamonds, the total number of diamonds is given by 8 × 1 + 12 × (6 - 2) + 6 × 3 = 74, because there are 8 corners, 12 edges and 6 faces.


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