Did you solve it? The Zorro puzzle

In my puzzle column earlier today I set you these problems about slicing through a square grid: 1) What is the least number of straight lines you need to draw across a 3×3 square grid so that every cell in the grid has at least one of the lines passing through it. 2) What is…

Can you solve it? The Zorro puzzle

Today you’re going to get the chance to prove a theorem no one has ever proved before. First, the basic puzzle: What is the least number of straight lines you need to draw across a 3×3 square grid (illustrated left) so that every cell in the grid has at least one of the lines passing…

Letter: Rosamund Sutherland obituary

Rosamund Sutherland undertook important work on the teaching of algebra in schools. The report that she produced in 1997 as the chair of the Royal Society/Joint Mathematical Council working group was influential in shaping the 1999 national curriculum review in mathematics. I was one of the members of the mathematics team at the Qualifications and…