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.