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Question P3 Rectangle and square measurement

find rectangle area

Find the area of the shown 8 cm by 5 cm rectangle.

A rectangle with its side lengths marked.8 cm5 cm

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About this method

Rectangle and square measurement

Use opposite equal sides, undo the area or perimeter formula, and count each outside edge once.

In this one. Rectangle area counts the unit squares in its rows and columns.

Undo or tracearea48 split into rows of 8 gives width 6perimeterfour equal square sides

How to spot it

Squares tiling a rectangle, or a shape made of several rectangles joined together, point here. The question asks for area, perimeter, or the length of a missing side.

Common mistake

Children multiply length by width when the question actually asks for perimeter. On a composite shape, they add only the labelled sides and miss the ones they must work out themselves.

Practise a similar question

Standard The shown 8-by-5 rectangle is covered with square tiles. Does the number of tiles describe its area or its perimeter?
All 14 with this pattern →
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