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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.

Brothers and Sisters

Stage: 2 Challenge Level: Challenge Level:1

Why do this problem?

This problem encourages children to use number operations and either trial and improvement, or a systematic approach to reach a solution. It would be interesting to share the different ways they use jottings to help during the problem-solving process. The problem could be used to introduce algebraic notation.

Key questions

What could you try to start with?
What does that tell you about the ages of the other children?
What do you know about David's age compared with Lachlan's age?

Possible extension

Learners could make up another similar problem for a friend to solve.

Possible support

You could ask questions such as 'what if Lachlan is one year old?' and encourage children to work out the ages of Cassandra and David to see whether all the information holds true. If not, invite learners to suggest what to try next.