problem
Favourite
That number square
Exploring the structure of a number square: how quickly can you put the number tiles in the right place on the grid?
Can you put the numbers 1-5 in the V shape so that both 'arms' have the same total?
In this 100 square, look at the green square which contains the numbers 2, 3, 12 and 13. What is the sum of the numbers that are diagonally opposite each other? What do you notice?
Who said that adding, subtracting, multiplying and dividing couldn't be fun?