Compare Angle Sizes

This activity is about identifying the largest and smallest angles.

We can identify angles as follows: right angles (90 degrees), acute angles (smaller than a right angle), or obtuse angles (larger than a right angle).

Example

Identify the largest and smallest angles.

1 2  3

Answer

The smallest angle is 1.  It is smaller than a right angle, so we call this an acute angle.

The largest angle is 2.  It is larger than a right angle, so we call this an obtuse angle.

Angle 3 is a right angle. 

It is smaller than angle 2 but larger than angle 1.

We can spot a right angle by imagining the corner of a square or rectangle.

Also, right angles are often labelled with a square corner, like the one in this example. 

Shall we have a go at some questions now?