Probability chapter rescued

I am delighted to day that at the last minute my publisher has agreed that we should reinstate the chapter on Probability in the 5th edition of Mathematics Explained for Primary Teachers (see my post on this site on 23 December). We were alerted to the fact that the enlightened Welsh and Scottish primary curriculums still include probability - and the book serves the other UK countries as well as England. And, of course, there are plenty of academies and free schools who do not have to follow the National Curriculum (ironic, isn't it!), so we want to make sure that teachers in these schools have the opportunity to understand this most important and interesting application of mathematics and to consider exploring it with the children they teach.

Now here's an intriguing use of numbers that turned up at home recently. I said to Mrs H, 'What's four plus one?' She replied, 'Thirteen'. She was right, of course. Can you explain?

And, finally, just to grab a little reflected glory: the amazing Jon Haylock doing astounding things around the Welsh coast with Griff Rhys-Jones on ITV this evening (8 pm) is my nephew.