Step 5 Objective
Recognise the first few triangular numbers, squares of numbers to at least 12 × 12 and the corresponding roots.
- Examples of what pupils should
know and be able to do - Probing questions
- What if pupils find
this a barrier?
Probing questions
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Two square numbers have a sum of 90.
What are they?
Find the first two square numbers that are also triangular.
Explain how to find the triangular numbers.