Short Problems
Quiz Questions
Jack does a 20-question quiz. How many questions didn't he attempt?
Jenny's Logic
Weekly Problem 52 - 2009
How did Jenny figure out that Tom's cards added to an even number?
Mini Kakuro
The sum of each column and row in this grid give the totals as shown. What number goes in the starred square?
Newspaper Sheets
From only the page numbers on one sheet of newspaper, can you work out how many sheets there are altogether?
Central Sum
Can you find numbers between 100 and 999 that have a middle digit equal to the sum of the other two digits?
12345
Repeat a pattern of numbers to form a larger number. Can you find the sum of all the digits?
Digit Deletion
What is the largest number of digits that could be erased from this 1000-digit number, to get a surprising result?
Alberta's Age
Alberta won't reveal her age. Can you work it out from these clues?
Double with 1 to 9
Can you find a number and its double using the digits $1$ to $9$ only once each?