Metric and imperial units

problem
Illusion

Age

11 to 16

Challenge level

A security camera, taking pictures each half a second, films a cyclist going by. In the film, the cyclist appears to go forward while the wheels appear to go backwards. Why?
problem
Watching the wheels go 'round and 'round

Age

7 to 11

Challenge level

Use this information to work out whether the front or back wheel of this bicycle gets more wear and tear.
problem
At the pumps

Age

7 to 11

Challenge level

How will you find out how much a tank of petrol costs?
problem
Weighing fruit

Age

7 to 11

Challenge level

Can you use this information to estimate how much the different fruit selections weigh in kilos and pounds?
problem
A day with Grandpa

Age

7 to 11

Challenge level

Grandpa was measuring a rug using yards, feet and inches. Can you help William to work out its area?
problem
Olympic measures

Age

11 to 14

Challenge level

These Olympic quantities have been jumbled up! Can you put them back together again?
problem
All in a jumble

Age

11 to 14

Challenge level

My measurements have got all jumbled up! Swap them around and see if you can find a combination where every measurement is valid.
problem
Triathlon and fitness

Age

11 to 14

Challenge level

The triathlon is a physically gruelling challenge. Can you work out which athlete burnt the most calories?
problem
Robot camera

Age

14 to 16

Challenge level

Could nanotechnology be used to see if an artery is blocked? Or is this just science fiction?