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?
A game that tests your understanding of remainders.
Weekly Problem 29 - 2011
From only the page numbers on one sheet of newspaper, can you work out how many sheets there are altogether?
In a square in which the houses are evenly spaced around the
outside, numbers $3$ and $10$ are opposite each other.
What is the smallest number of houses in the square?
What is the largest possible number of houses in the square?