Quarter the Cross

At the end of last year, the MTBoS (Math(s) Twitter Blog-o-Sphere) introduced me to this very interesting task: you have a cross made of four equal squares, and you are supposed to colour in exactly 1/4 of the cross and justify why you know it's a quarter. I call it "Quarter the Cross".

You can read the rest of this blog post, and four other related posts, in PDF form here

The titles of the five posts in the series are:

• Quarter the Cross (2016)
• A Day of Maths: Quarter the Cross (2016)
• David Butler and the Prisoner of Alhazen (2016)
• Quarter the Cross: Colouring (2020)
• Quarter the Cross: Connect the Dots (2020)

Some resources linked from this post:

• High resolution picture of my 100 solutions (PNG 4MB)
• Original vector graphics file of my 100 solutions (SVG)
• Handout version with five small crosses (Word)
• Handout version with one big cross (Word)