Try to stop your opponent from being able to split the piles of counters into unequal numbers. Can you find a strategy?
Investigate the smallest number of moves it takes to turn these mats upside-down if you can only turn exactly three at a time.
Can you find examples of magic crosses? Can you find all the possibilities?
I added together some of my neighbours' house numbers. Can you explain the patterns I noticed?
Place the numbers 1, 2, 3,..., 9 one on each square of a 3 by 3 grid so that all the rows and columns add up to a prime number. How many different solutions can you find?
Great Granddad is very proud of his telegram from the Queen congratulating him on his hundredth birthday and he has friends who are even older than he is... When was he born?
Weekly Problem 52 - 2009
How did Jenny figure out that Tom's cards added to an even number?
Find the sum, f(n), of the first n terms of the sequence: 0, 1, 1, 2, 2, 3, 3........p, p, p +1, p + 1,..... Prove that f(a + b) - f(a - b) = ab.
