The digits 1-9 have been written in the squares so that each row and column sums to 13. What is the value of n?
An examination paper is made from five pieces of paper. What is the sum of the other page numbers that appear on the same sheet as page 5?
Weekly Problem 39 - 2010
If you know three lengths and an angle in this diagram, can you find another angle by calculation?
Three circles of different radii each touch the other two. What can you deduce about the arc length between these points?
Each interior angle of a particular polygon is an obtuse angle which is a whole number of degrees. What is the greatest number of sides the polygon could have?
Find out how many pieces of hardboard of differing sizes can fit through a rectangular window.
What is the first term of a Fibonacci sequence whose second term is 4 and fifth term is 22?
The diagram shows two circles and four equal semi-circular arcs. The area of the inner shaded circle is 1. What is the area of the outer circle?
How many different phone numbers are there starting with a 3 and with at most two different digits?
Walking up a steep hill, I pass 10 equally spaced street lamps. How long do I take to walk from the first lamp to the last?
