Weekly Problem 25 - 2009

Jack does a 20-question quiz. How many questions didn't he attempt?

Gar the Magician plays a card trick on his friends Kan and Roo. Can you work out his trick and find out the sum on Kan's cards?

The sum of each column and row in this grid give the totals as shown. What number goes in the starred square?

Weekly Problem 29 - 2011

From only the page numbers on one sheet of newspaper, can you work out how many sheets there are altogether?

Weekly Problem 53 - 2011

Find a number between 100 and 999 that has its middle digit equal to the sum of the other two digits. Can you find all possibilities?

Weekly Problem 50 - 2011

Repeat a pattern of numbers to form a larger number. Can you find the sum of all the digits?

Weekly Problem 14 - 2010

What is the largest number of digits that could be erased from this 1000-digit number, to get a surprising result?

Weekly Problem 26 - 2011

Alberta won't reveal her age. Can you work it out from these clues?

Weekly Problem 31 - 2011

Can you find a number and its double using the digits $1$ to $9$ only once each?