Consecutive Numbers

An investigation involving adding and subtracting sets of consecutive numbers. Lots to find out, lots to explore.

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...

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.