Teaching mathematics

2.2 Indeterminacy: moving from specific unknowns to variables

When learners are introduced to symbolic representations, they often represent a quantity that has a specific but unknown value. The learner may be asked to find this value.

Two examples of such problems are missing number problems and Think of a Number (THOAN) problems.

Activity 7 Missing number problems

Allow 10 minutes

Have a go at the following problems.

Figure 4 Missing number problems

Activity 8 Reflecting

Allow 5 minutes

What makes these algebra problems, rather than simply number problems?

What do you expect learners to learn from these problems?

Now watch the two videos that discuss these questions.

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Video 3 Missing number problems
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Video 4 THOAN