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Domino Square

Use the 'double-3 down' dominoes to make a square so that each side has eight dots.

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The Puzzling Sweet Shop

There were chews for 2p, mini eggs for 3p, Chocko bars for 5p and lollypops for 7p in the sweet shop. What could each of the children buy with their money?

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Sandwiches

Arrange the digits 1, 1, 2, 2, 3 and 3 so that between the two 1's there is one digit, between the two 2's there are two digits, and between the two 3's there are three digits.

Plenty of Pens

Stage: 2 Challenge Level: Challenge Level:1

Why do this problem?

This problem can be approached in several different ways (by randomly trying numbers, working in a systematic way to try numbers, making a table) and could be a nice way of introducing algebra.

Key questions

What do we know?
What could we try first?
How many pencils might she have bought? How many pens would that mean she'd bought?
What could we try next?

Possible extension

Learners could try Buckets of Thinking which involves similar mathematics.

Possible support

Using real pencils and pens may help children keep track of what they have tried.

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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NRICH is part of the family of activities in the Millennium Mathematics Project.