Catch this bug! The Critical Line – Volume 22

Following a record-breaking round of solutions sent in for Jevon’s Critical Line last month, Oliver follows up with a creepy crawly puzzle for you.

Three blind spiders and a bug live on the edges of a wire tetrahedron (a triangular base pyramid).

The spiders would like to catch the bug, but they do not know where the bug is and they cannot see it. However, if they run into the bug they will feel it and eat it.

The bug wants to avoid the spiders, it knows where they are and where they will travel in the future. The spiders can work together, and they have one advantage – they’re faster than the bug.

What strategy do the spiders have to guarantee that they can catch the fly?

For your chance to win a $50 book voucher, send your solutions to


Solution to Critical Line 21 – by Jevon Fulbrook

It was amazing to get an incredible 16 entries last month! The first successful solution was from Jess Twigg, congrats!

Solution below:


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