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# Imagining missing elements

Missing elements may be numbers, shapes, variables or other mathematical objects.

They are used to:

- balance or solve equations
- predict terms in number sequences or series and sequences
- complete patterns, tables and arrays
- solve problems.

Mathematical reasoning is needed to describe and identify missing elements.

Missing elements may be used in teaching and assessment. The activity *Covered by H* is easy to adapt for all year levels.

## Covered by H

This activity focusses on horizontal and vertical place-value patterns in a number grid. A shape is used to cover parts of the grid. Students need to explain what the covered numbers are and how they know.