Book Codes

Look on the back of any modern book and you will find an ISBN code. Take this code and calculate this sum in the way shown. Can you see what the answers always have in common?

Weekly Problem 25 - 2006

Weekly Problem 25 - 2006

Weekly Problem 5 - 2007

When coins are put into piles of six 3 remain and in piles of eight 7 remain. How many remain when they are put into piles of 24?

Neighbours

Stage: 2 Challenge Level:
If the houses are evenly spaced, what do you know about the total number of houses?
Where could house number $1$ go?
Have you thought of drawing a picture?