Grid Investigation
1) Is it possible on the
simplest grid (12 matches) to arrange the matches so that rows columns and 
diagonals are equal?
2) With the 24 match grid it
is possible to equalise rows, columns and diagonals. Keeping the rows and
columns equal find out how the diagonals can be arranged to have the same
number of heads. What is the largest number of heads, what is the smallest that
can lie in both diagonals?
3) Investigate the 4 by 4
grid with 40 matches. Can you equalise rows, columns and diagonals? Keeping the rows and columns equal what
values can be in the diagonals?