Working systematically

problem

Olympic Magic

Age

14 to 16

Challenge level

2 out of 3

in how many ways can you place the numbers 1, 2, 3 … 9 in the nine regions of the Olympic Emblem (5 overlapping circles) so that the amount in each ring is the same?
problem

Magic W

Age

14 to 16

Challenge level

2 out of 3

Find all the ways of placing the numbers 1 to 9 on a W shape, with 3 numbers on each leg, so that each set of 3 numbers has the same total.
problem

Tetrahedra Tester

Age

14 to 16

Challenge level

2 out of 3

An irregular tetrahedron is composed of four different triangles. Can such a tetrahedron be constructed where the side lengths are 4, 5, 6, 7, 8 and 9 units of length?
problem

Facial Sums

Age

14 to 16

Challenge level

2 out of 3

Can you make the numbers around each face of this solid add up to the same total?
problem

No Square Sums

Age

14 to 16

Challenge level

2 out of 3

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

Alberta's Age

Age

14 to 16

Challenge level

2 out of 3

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

The Fastest Cyclist

Age

14 to 16

Challenge level

2 out of 3

Andy is desperate to reach John o'Groats first. Can you devise a winning race plan?
problem

Relative Time

Age

14 to 16

Challenge level

2 out of 3

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

Alphabetical Angle

Age

14 to 16

Challenge level

2 out of 3

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

Switch On

Age

14 to 16

Challenge level

2 out of 3

In how many different ways can a row of five "on/off" switches be set so that no two adjacent switches are in the "off" position?