St. Joseph's School School Otahuhu


Room 1


Cut the Cake!

Can you cut a round, single layered cake into 8 equal pieces?  Of course I can you’re saying!

Think again – you have to cut it into 8 equal pieces, BUT you may only make THREE cuts. 

That’s when things became a little challenging for us in our teams.  The good news is we had heaps of fun, and the bonus was we solved the problem and rewarded ourselves with an eighth of the chocolate cake our team had cut.

This is what we did to solve the problem:


In our teams of 8 we used vivids and a large piece of paper to discuss and try and draw out how we would approach the problem.  This took some thinking and we came up with quite a few ideas – have a look at the photos to see our thinking.


Once we thought we had the problem sorted, we used playdough in our teams to try out our theories.  This was not only fun, but we were able to see more clearly what the outcomes of our drawings were and therefore if it would work when we cut the cake.  

All the teams came to the same solution initially, again look at the photos to see if you are able to identify what we did.

Mrs Massari was impressed with our first solution, but said that we now needed to try solving it another way.  This was way more challenging and really required additional creative thinking.  

Some of us returned to our initial ideas and drew out a few more…

Here’s what happened  using playdough:  

Team 1:   Empres had a eureka moment…well, actually a Gordon Ramsey moment when she said to cut the playdough like we learnt to cut the pita pockets at manual, then cut it in quarters…that’ll give us 8 pieces!!  Yay!

Team 2:   Pine has a eureka moment when she had a careful, intrigued look at the cake from the side and suddenly gestured to slice it right through the middle…then cut it in quarters …resulting in 8 equal pieces for her team!!  Success!

Team 3:   Verozzi and team listened carefully to Mrs Massari suggesting to draw a 3D cake, then to questions such as where does one ice a cake (on top), where else (around the sides), anywhere else??   Here’s where the eureka moment came for this group – Verozzi suddenly visualised the cake with icing in the middle…needless to say, the team immediately sliced the cake through the middle…then in quarters and of course with two layers they too had 8 equal pieces!!   Yes we can!!


We cut out cakes and discovered both solutions were correct, most groups decided to use the method of lining up slices and cutting them through, instead of slicing through the center of the cake – this was because we felt we’d each end up with ‘more of an equal piece’ that way.