Working systematically

problem
Orange drink

Age

7 to 11

Challenge level

A 750 ml bottle of concentrated orange squash is enough to make fifteen 250 ml glasses of diluted orange drink. How much water is needed to make 10 litres of this drink?
problem
Uncanny triangles

Age

7 to 11

Challenge level

Can you help the children find the two triangles which have the lengths of two sides numerically equal to their areas?
problem
Chocoholics

Age

7 to 11

Challenge level

George and Jim want to buy a chocolate bar. George needs 2p more and Jim need 50p more to buy it. How much is the chocolate bar?
problem
Satnav dilemma

Age

11 to 14

Challenge level

How many routes are there in this diagram from S to T?
problem
Robot monsters

Age

5 to 7

Challenge level

Use these head, body and leg pieces to make Robot Monsters which are different heights.
problem
Polo square

Age

7 to 11

Challenge level

Arrange eight of the numbers between 1 and 9 in the Polo Square below so that each side adds to the same total.
problem
On the edge

Age

11 to 14

Challenge level

If you move the tiles around, can you make squares with different coloured edges?
problem
Tangram tangle

Age

5 to 7

Challenge level

If you split the square into these two pieces, it is possible to fit the pieces together again to make a new shape. How many new shapes can you make?
problem
Cuboids

Age

11 to 14

Challenge level

Can you find a cuboid that has a surface area of exactly 100 square units. Is there more than one? Can you find them all?
problem
Ben's game

Age

11 to 16

Challenge level

Ben, Jack and Emma passed counters to each other and ended with the same number of counters. How many did they start with?