Figure Classification (Odd One Out) for the Assam Police Constable (AB & UB) Exam
Figure Classification, also called odd one out, is a non-verbal reasoning topic of the SLPRB Assam Police Constable (AB & UB) examination in which a group of figures is shown and the candidate must find the one figure that does not share the common property of the group. The topic tests classification, that is the ability to see the common feature of most figures and to detect the single exception. No general knowledge and no language skill are needed; the whole question is solved by finding the property that four or more figures share and then spotting the figure that lacks it. A candidate who tests each figure against the group property almost never makes a mistake. This page explains the bases of classification, the worked examples, the shortcuts and the traps that cost marks. The material follows the standard reasoning reference books used for Assam recruitment examinations and is reviewed before it is published.
What the Topic Means
In classification a group of usually four or five figures is given, and all of them except one are alike in some way. The candidate must find the common property, such as the number of sides, the number of parts, the type of symmetry, or the presence of a particular element, and then choose the figure that breaks the property. The odd figure is odd only with respect to that property and may look like the others in every other way. The candidate must therefore decide which property is being used before selecting the answer.
The Common Bases of Classification
- Number of sides or of angles in the figure.
- Number of parts, lines, dots or curves in the figure.
- Presence or absence of symmetry, and the type of symmetry.
- Open or closed figure, or a figure made of straight lines against one made of curves.
- Position, orientation or rotation of the same figure.
- Shading, filling or colour of the figure.
- Partition of the figure, such as a square divided into four equal parts.
- Presence of a repeated element, such as two dots in every figure except one.
A Step by Step Method
- Look at all the figures together and try to find one common property.
- Check whether the property holds for all the figures except one.
- If the property fits four figures out of five, the remaining figure is the answer.
- If no single property fits, try a second basis such as the number of parts or symmetry.
- Confirm the odd figure by testing it against the chosen property once more.
- Choose the option that matches your conclusion and reject the look-alike options.
Worked Examples
Example one: four figures are triangles and one is a square, so the square is the odd one out because it has four sides. Example two: four figures are closed shapes and one is an open shape, so the open shape is odd. Example three: four figures have a vertical line of symmetry and one has none, so the one without symmetry is odd. Example four: four figures are divided into equal parts and one is divided into unequal parts, so the unequal figure is odd. Example five: four figures each contain two dots and one contains three, so the figure with three dots is odd.
How This Topic Appears in the Examination
The topic usually appears as two to four objective questions of one mark each. The common forms are to find the odd figure from a group of four or five, to find the figure that does not belong to the given set, and to select the figure that is different from the rest. Since all the figures look similar, the candidate must judge by a definite property and not by appearance.
Shortcuts and Speed Methods
- Count the sides, angles, lines and parts of each figure first, as counting solves most questions.
- Check symmetry and the open or closed nature of the figures next.
- Think of the property that the majority share, not of the property of a single figure.
- If one property fits four of five figures, stop at once; do not look for another property.
- Reject tempting options that are odd only in a minor, unimportant way.
Common Mistakes to Avoid
- Choosing the figure that looks different without testing a property.
- Using a property that fits only two or three figures and not the majority.
- Overlooking the number of small parts inside the figure.
- Confusing an odd figure with a figure that is merely rotated.
- Ignoring the type of symmetry and looking only at the outer shape.
Preparation Plan
- Learn the list of common bases of classification by heart.
- Practise twenty classification questions a day, naming the common property each time.
- Separate the practice of counting bases, symmetry bases and shading bases.
- Time yourself so that each question takes less than a minute.
- Revise the common bases once a week until they are recognised at a glance.
More Practice Questions
- Four figures with three sides each and one with four sides, so the four-sided figure is odd.
- Four figures with a curved boundary and one with a straight boundary, so the straight one is odd.
- Four figures shaded inside and one shaded outside, so the outside-shaded figure is odd.
- Four figures having a horizontal line of symmetry and one having only a vertical line, so the vertical one is odd.
- Four figures made of one continuous line and one made of two separate lines, so the two-line figure is odd.
Quick Revision Checklist
- Look for a property shared by the majority of figures.
- Count sides, angles, parts and dots first.
- Check symmetry, open or closed, and shading next.
- The figure that breaks the majority property is the answer.
- Do not be misled by figures that differ only by rotation.
Frequently Asked Questions
What is figure classification?
It is a non-verbal reasoning topic in which a group of figures is given and the candidate must find the one figure that does not share the common property of the group.
What properties are used?
The number of sides, angles, parts or dots, the presence and type of symmetry, the open or closed nature of the figure, its shading, and the partition of the figure are the usual properties.
How do I decide the common property?
Look at all the figures together and find the property that fits the majority; the single figure that does not fit it is the odd one out.
What if two properties seem to fit?
Choose the property that fits the larger number of figures, because the odd figure is odd only with respect to the true common property of the group.
Is figure classification scoring in Assam Police?
Yes. Each question is solved by one property that can be counted or seen, so it is a reliable place to gain marks in the reasoning paper.