Find a great variety of ways of asking questions which make 8.
Choose any three by three square of dates on a calendar page.
Circle any number on the top row, put a line through the other
numbers that are in the same row and column as your circled number.
Repeat this for a number of your choice from the second row. You
should now have just one number left on the bottom row, circle it.
Find the total for the three numbers circled. Compare this total
with the number in the centre of the square. What do you find? Can
you explain why this happens?
Use the 'double-3 down' dominoes to make a square so that each side has eight dots.
My calculator has 26 memories - one per letter of the alphabet.
When I type a sequence of letters the calculator gives the product
of all the numbers in the corresponding memories. I want to put
numbers in the various stores so that when I type the word ONE it
returns 1, and when I type the word TWO it returns 2, and when I
type the word THREE it returns 3 and so on. How far can you get ?
Is there an integer above which it is impossible to get ?