http://www.cut-the-knot.org/do_you_know/cake.shtml

How is that possible when the formula for this is 1/2(n^2 + n + 2)?

The max number of pieces is 7, isnt it?

>http://www.cut-the-knot.org/do_you_know/cake.shtml
>
>How is that possible

Well, this is what this page is about. Have not you read it?

The formula you cite relates to a sequence of vertical cuts. The 3 cuts solution does not fit into this framework because one of the cuts is horizontal.

Dont know what I'm doing wrong but the most I can get is 7.

3 lines like this?

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Have no idea why im not getting this, it seems simple enough.

>Have no idea why im not getting this, it seems simple
>enough.

Right. If you cut 4 of something (sausages, say) put side by side so that you are able to cut all 4 with one cut, you get 8 pieces.

Unquestionably, you can cut the pie into 4 pieces with 2 cuts. Imagine now the pie put on a side, so that all 4 pieces become exposed to a vertical cut. Do it.

The 8 pieces you obtain are not exactly what one would expect: 4 come from the bottom of the pie, 4 from the top. The latter carry all the toppings and, in all likelihood, are more desirable. The former may be less hazardous to one's health, though.

Someone asked me this and the best answer I got was cut the pie in half, stack the halves on top of each other, cut that in half, and then stack the quarters on top of each other, then cut that in half. Thus you get 8 pieces with 3 cuts. Though I'm not sure if stacking the pieces is exactly legal. Since I never found out the answer to the riddle.

Pete

This thread is exactly about this problem. Just read it. Ot have a look at

http://www.cut-the-knot.org/do_you_know/cake.shtml