Odd One Out (Shapes)

Welcome to your first Non-Verbal Reasoning lesson! In Odd One Out questions, you are given a set of five shapes (or pictures) and you must find the one that does not belong with the others. The four shapes that belong together all share something in common — your job is to spot the rule that connects them and find the shape that breaks it.

This is one of the most common question types in the GL 11+ exam, so mastering it will give you a real head start.

What Is an Odd One Out Question?

Imagine you have five shapes in a row:

Shape A: A large black circle
Shape B: A large black square
Shape C: A large black triangle
Shape D: A small white circle
Shape E: A large black pentagon

Four of these shapes share something in common. Can you spot the odd one out?

Answer: Shape D is the odd one out. Shapes A, B, C, and E are all large and black. Shape D is small and white — it breaks both rules.

The Key Strategy: Look for Rules

When you see an Odd One Out question, you need to check each shape for different properties. Here are the main properties to look for:

1. Shape Type

Property	Examples
Straight sides	Squares, triangles, rectangles, pentagons
Curved sides	Circles, ovals, semicircles
Number of sides	3 sides, 4 sides, 5 sides, 6 sides

Ask yourself: "Are most of the shapes the same type? Does one have a different number of sides?"

2. Size

Shapes can be large, medium, or small. If four shapes are the same size and one is different, that could be your answer.

3. Shading and Fill

Fill type	What it looks like
Black / solid	Completely filled in
White / empty	Just an outline, nothing inside
Striped	Lines running across the shape
Dotted	Small dots filling the shape
Grey	A lighter shade of fill

4. Orientation and Rotation

A shape might be rotated (turned) compared to the others. For example, four arrows might point up and one might point down.

5. Line Style

Line style	What it looks like
Solid line	A continuous line ———
Dashed line	A broken line - - - -
Thick line	A wider, bolder line
Thin line	A narrow, fine line

6. Number of Shapes

Sometimes each option contains more than one shape. Four options might have two shapes inside them, while one option has three.

7. Position of Elements

If each option has a small shape inside a larger shape, check whether the small shape is in the same position (top, bottom, centre, left, right) in each one.

Worked Example 1

Shape A: A white triangle with a black dot in the centre
Shape B: A white square with a black dot in the centre
Shape C: A white pentagon with a black dot in the centre
Shape D: A white hexagon with a black dot at the top
Shape E: A white circle with a black dot in the centre

Step 1: Look at the outer shapes — triangle, square, pentagon, hexagon, circle. They are all different, so shape type is probably not the rule.

Step 2: Look at the fill — all outer shapes are white. No difference there.

Step 3: Look at what is inside — all have a black dot. Same so far.

Step 4: Look at the position of the dot — A, B, C, and E all have the dot in the centre. Shape D has the dot at the top.

Answer: Shape D is the odd one out because the dot is not in the centre.

Worked Example 2

Shape A: A large black right-angled triangle
Shape B: A large black equilateral triangle
Shape C: A large black isosceles triangle
Shape D: A large black square
Shape E: A large black scalene triangle

Step 1: Look at the shape type — A, B, C, and E are all triangles (3 sides). Shape D is a square (4 sides).

Answer: Shape D is the odd one out because it has 4 sides while all the others have 3 sides.

Worked Example 3 (Tricky!)

Shape A: A circle divided into 2 equal halves, left half black
Shape B: A square divided into 2 equal halves, left half black
Shape C: A triangle divided into 2 equal halves, left half black
Shape D: A pentagon divided into 2 equal halves, right half black
Shape E: A hexagon divided into 2 equal halves, left half black

Step 1: All shapes are different types — circle, square, triangle, pentagon, hexagon. That is fine.

Step 2: All are divided into 2 halves — same so far.

Step 3: Check which half is black. In A, B, C, and E, the left half is black. In D, the right half is black.

Answer: Shape D is the odd one out because it has the right half shaded instead of the left.

Top Tip: The tricky Odd One Out questions often test small details like position, orientation, or shading direction — not just the obvious things like shape type.

Common Traps to Watch Out For

Obvious but wrong: Sometimes one shape looks very different (e.g., it is a different colour) but it still follows the main rule. Do not pick the most "different-looking" shape — pick the one that breaks the rule.
Multiple properties: The rule might combine two properties. For example, "all shapes are large AND have stripes" — the odd one out might be large but without stripes.
Counting: Count sides, dots, lines, or sections carefully. A pentagon (5 sides) and a hexagon (6 sides) can look very similar if you rush.

Your Step-by-Step Checklist

Use this checklist every time you tackle an Odd One Out question:

Check the shape type (number of sides, curved vs straight)
Check the size (large, medium, small)
Check the shading/fill (black, white, grey, striped, dotted)
Check the line style (solid, dashed, thick, thin)
Check the orientation/rotation (which way is it pointing?)
Check internal elements (dots, lines, smaller shapes inside)
Check the position of internal elements (centre, top, bottom, left, right)
Check the number of elements in each option

Practice Approach

When you practise Odd One Out at home:

Time yourself — try to answer each question in about 30 seconds.
Talk through your thinking — say the rule out loud (e.g., "Four shapes have 4 sides, one has 3 sides").
If you are stuck, try covering one shape at a time and asking: "Do the remaining four all match?"
Review your mistakes — when you get one wrong, write down what property you missed.

Key Terms

Term	Meaning
Property	A feature of a shape, such as its size, colour, or sides
Rule	The common feature shared by four of the five shapes
Odd one out	The shape that does not follow the rule
Orientation	The direction a shape is pointing or facing
Shading	How a shape is filled in (solid, empty, striped, etc.)

Summary

Odd One Out questions test your ability to spot patterns and rules. Always check multiple properties — shape type, size, shading, line style, orientation, internal elements, and position. The answer is the shape that breaks the rule the other four follow. Work systematically, and you will get faster with practice!