I'm Eight

Find a great variety of ways of asking questions which make 8.

Calendar Capers

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?

Domino Square

Use the 'double-3 down' dominoes to make a square so that each side has eight dots.

Arrange the Digits

Stage: 3 Challenge Level:

The solution refers to digital roots of nine. This document gives some explanation of why, whatever the order of the digits $1-9$, the total will always be a digital root of nine.