[Prof. Templeton]

For Christmas my kids had received a set of 26 wooden blocks, one for every letter of the alphabet. While playing with my children I would make various shaped towers and walls out of the blocks that they took great delight in demolishing. During one of my building sprees I was thinking back to stacking oranges and wondered if I could make a square pyramid out of the blocks. Certainly I could make one with a 3x3 base, but that would only need 14 blocks, leaving a lot of unused blocks. After some thought I made a square pyramid with a 4x4 base that ended with 1 block on top using only the blocks I had available (which my daughter promptly kicked into oblivion with much glee). How would such a structure be built?

[Guest]

hollow

that is, make a 4x4 square for the base, using 12 blocks. Add a 3x3 square (balance carefully, now) out of 8 blocks. The next layer has 4 blocks and one on top. 25 blocks leaves one left over for your daughter to throw at the pyramid. And the hollow-ness makes is easy to demolish. yippee!

Edited January 5, 2009 by Cherry Lane

[Prof. Templeton]

hollow

that is, make a 4x4 square for the base, using 12 blocks. Add a 3x3 square (balance carefully, now) out of 8 blocks. The next layer has 4 blocks and one on top. 25 blocks leaves one left over for your daughter to throw at the pyramid. And the hollow-ness makes is easy to demolish. yippee!

Hollow, the sides of the 3x3 would fall into the middle of the 4x4 layer.

[Guest]

Hollow, the sides of the 3x3 would fall into the middle of the 4x4 layer.

precarious, I admit, but with the right balance and help from friction with the corner pieces it can work.

[Guest]

Hollow, the sides of the 3x3 would fall into the middle of the 4x4 layer.

precarious, I admit, but with the right balance and help from friction with the corner pieces it can work.

...I'd take it away from the daughter (don't need any more pointy projectiles in my house) and place it in the hollow space in the bottom level, rotated at 45° so each corner will support each middle side piece of the 3x3 level.

[Guest]

...I'd take it away from the daughter (don't need any more pointy projectiles in my house) and place it in the hollow space in the bottom level, rotated at 45° so each corner will support each middle side piece of the 3x3 level.

that would make it more stable...but less fun for the daughter

[Guest]

Then how about this ?

[Prof. Templeton]

...I'd take it away from the daughter (don't need any more pointy projectiles in my house) and place it in the hollow space in the bottom level, rotated at 45° so each corner will support each middle side piece of the 3x3 level.

That was it.

rotated block placed in the center of the hollow 4x4 layer would hold up the side blocks of the hollow 3x3 layer and the 2x2 would sit on top of that with no center support needed and the single block on top. After construction the pyramid stood

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