A bag contains 12 marbles. There are more red than green but green
and blue together exceed the reds. The total of yellow and green
marbles is more than the total of red and blue. How many of each
colour there are in the bag?
Age 11 to 14 Challenge Level:
Is there a quick way to work out the totals without having to add everything up?
If you know just one date in your three by three square, how can you work out the other eight dates?
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.