Volume 47
, Issue 3


Welcome to a packed issue to close the year in 2011.
Congratulations to all of the students, their parents and teachers who had success in the 50th Annual UNSW School Mathematics Competition.
This article is fundamentally about the calculations behind the ways in which computers draw graphs. In the era before computers (unknown to most of you, but very familiar to me!) graphs were drawn on paper. Typically, the data points were plotted.
Let me begin by recounting a story I first heard almost fifty years ago. This is, of course, a long time and over the intervening years I have lost contact with the people involved. So it may well be that I have misremembered parts of it and the actual event may well have been somewhat different in its details.
Many readers will at some time have played games with a pack of cards.  In most games one begins by shuffling the cards so as to randomise their order.  There are various different ways of shuffling, one of the most popular being the riffle shuffle.
Junior Division - Problems and Solutions
Problem 1
A second-cousin prime $n$-tuple is defined as a set of $n$ prime numbers  $\{p, p+6, \ldots p+6(n-1)\}$ with co
Competition Winners – Senior Division
First Prize
Edmond Cheng                                          Newington College
Q1371 Consider shuffles of a standard $52$-card pack.
Q1361 Find a six-digit number which can be split into three two-digit squares and also into two three-digit squares.