Convince Me!

Here are some challenges that you can work on and then see if you can convince someone that your solutions are right! Have a go!


Beads and Bags

Stage: 1 and 2 Challenge Level: Challenge Level:1

How could you put these three beads into bags? How many different ways can you do it? How could you record what you've done?

Fifteen Cards

Stage: 2 Challenge Level: Challenge Level:1

Can you use the information to find out which cards I have used?

Spot Thirteen

Stage: 2 Challenge Level: Challenge Level:1

Choose 13 spots on the grid. Can you work out the scoring system? What is the maximum possible score?

Cuisenaire Spirals

Stage: 2 Challenge Level: Challenge Level:1

Can you make arrange Cuisenaire rods so that they make a 'spiral' with right angles at the corners?

Money Bags

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Ram divided 15 pennies among four small bags. He could then pay any sum of money from 1p to 15p without opening any bag. How many pennies did Ram put in each bag?

Sealed Solution

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Ten cards are put into five envelopes so that there are two cards in each envelope. The sum of the numbers inside it is written on each envelope. What numbers could be inside the envelopes?

Magic Vs

Stage: 2 Challenge Level: Challenge Level:2 Challenge Level:2

Can you put the numbers 1-5 in the V shape so that both 'arms' have the same total?

More of Convince Me

Stage: 2

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. More information on many of our other activities can be found here.
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