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# Cake

Harshana Dias
Ranch Hand
Posts: 333
Q: How many cuts can a round cake have in order to get the maximum number of similar size pieces? justify the answer?

This is a famous interview question..well now most of candidates prepare that question before it asks in an interview but when your first time facing it in a interview its a pretty decent question to measure your analytical or the way of you thinking

Bear Bibeault
Author and ninkuma
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Posts: 64833
86
Depends how sharp the knife is.

Paul Clapham
Sheriff
Posts: 21107
32
This is of course the mathematical ideal cake, right? The one which doesn't break into crumbs as you cut it?

In which case there isn't a maximum number of similar-sized pieces. With n cuts you can always make 2n pieces, no matter how large n is.

Harshana Dias
Ranch Hand
Posts: 333
Paul Clapham wrote:This is of course the mathematical ideal cake, right? The one which doesn't break into crumbs as you cut it?

In which case there isn't a maximum number of similar-sized pieces. With n cuts you can always make 2n pieces, no matter how large n is.

opss yes...my mistake..question would be how many minimum cuts need to get equal size 8 pieces of the cake?

:D

chandan kumar mitwaa
Ranch Hand
Posts: 49
3

Arjun Abhishek
Ranch Hand
Posts: 57
Can you please explain how 3 cuts makes 8 pieces ?

Paul Clapham
Sheriff
Posts: 21107
32
The first cut divides the cake into two pieces. The second cut, which passes through both of those pieces, divides them into four pieces. The third cut, which passes through all four pieces, divides them into eight pieces.

Since this is the mathematical no-crumb cake, four cuts produce 16 pieces, five cuts produce 32 pieces... you should be getting the picture by now.

Janeice DelVecchio
Saloon Keeper
Posts: 1809
12
Paul Clapham wrote:The first cut divides the cake into two pieces. The second cut, which passes through both of those pieces, divides them into four pieces. The third cut, which passes through all four pieces, divides them into eight pieces.

Since this is the mathematical no-crumb cake, four cuts produce 16 pieces, five cuts produce 32 pieces... you should be getting the picture by now.

They are not similar sized pieces. Or if they are I need a diagram :wink:

Mike Simmons
Ranch Hand
Posts: 3076
14
They can be, if you are permitted to rearrange pieces in between cuts. Nothing in the problem statement seems to preclude this.

For the version of the problem requiring just eight pieces, it's possible to do this without rearranging pieces - if the top and bottom of the cake are identical. Or at least if they're similar enough that the eight octants can be considered "similar sized". For a cake with frosting, most of us would not consider pieces from the top to be equivalent to pieces from the bottom. but perhaps we're supposed to overlook that.

Bear Bibeault
Author and ninkuma
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Posts: 64833
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Give me a piece without frosting and someone gets hurt!