A shape is drawn on a centimetre grid. Write down the order of rotational symmetry of the shape.

Answer

The shape shown on the centimetre grid is a rectangle. A rectangle has a rotational symmetry of order 2. This means that the shape looks the same after rotating it by 180 degrees. If you rotate the rectangle by 90 degrees, it will not look the same (it will be stood on its shorter end if it was originally on its longer end). If you rotate it by 180 degrees, it will align with its original position. Another 180 degrees (which is a full 360-degree rotation) will bring it back to its original position. Therefore, there are two positions (180 degrees and 360 degrees, or 0 degrees) in a full 360-degree rotation where the shape appears identical to its starting orientation. Thus, the order of rotational symmetry is 2.