Working systematically

problem

No Square Sums

Age

14 to 16

Challenge level

How many numbers do you need to remove to avoid making a perfect square?
problem

Alberta's Age

Age

14 to 16

Challenge level

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

Double With 1 to 9

Age

11 to 14

Challenge level

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

Rolling Along the Trail

Age

11 to 14

Challenge level

What could be the scores from five throws of this dice?
problem

The Square of My Age

Age

11 to 14

Challenge level

Lauren and Thomas tell their ages in terms of sums of squares. Can you work out how old they really are?
problem

Bent Out of Shape

Age

14 to 18

Challenge level

An introduction to bond angle geometry.
problem

Relative Time

Age

14 to 16

Challenge level

Albert Einstein is experimenting with two unusual clocks. At what time do they next agree?
problem

Staircase Sum

Age

11 to 14

Challenge level

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?
problem

Alphabetical Angle

Age

14 to 16

Challenge level

If all the arrangements of the letters in the word ANGLE are written down in alphabetical order, what position does the word ANGLE occupy?
problem

Latin Multiplication

Age

11 to 14

Challenge level

Can you choose one number from each row and column in this grid to form the largest possibe product?