Andrew decorated 20 biscuits to take to a party. He lined them up and put icing on every second biscuit and different decorations on other biscuits. How many biscuits weren't decorated?
Age 5 to 7 Challenge Level
Try to "see" one shape moving over the other in your mind.
You could cut out the shapes in two different colours of tissue paper or cut up two overhead transparencies to test out your ideas. Or, you could try drawing the two shapes overlapping.
The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the
NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to
embed rich mathematical tasks into everyday classroom practice.