1 out of 3
How many ways are there of completing the mini-sudoku?
1 out of 3
Two of the numbers in a 4×4 magic square have been swapped. Can you work out the sum of these numbers?
1 out of 3
Can you work out the sum of the missing digits in this subtraction?
1 out of 3
Weekly Problem 31 - 2016
The diagram shows a grid of $16$ identical equilateral triangles. How many rhombuses are there made up of two adjacent small triangles?
1 out of 3
Two of the four small triangles are to be painted black. In how many ways can this be done?
1 out of 3
In the multiplication table on the right, only some of the numbers have been given. What is the value of A+B+C+D+E?
2 out of 3
Your partner chooses two beads and places them side by side behind a screen. What is the minimum number of guesses you would need to be sure of guessing the two beads and their positions?
2 out of 3
In how many distinct ways can six islands be joined by bridges so that each island can be reached from every other island...
2 out of 3
In this addition each letter stands for a different digit, with S standing for 3. What is the value of YxO?
2 out of 3
A 1×2×3 block is placed on an 8×8 board and rolled several times.... How many squares has it occupied altogether?
