In this article, we cover the important dimensions related to CAT mensuration. All important aspects related to the topic are covered here and you will understand how to approach this topic.

These are four essential points that you need to keep in mind for this topic:

**Practice, practice and more practice:**Like any other area, this area too needs a lot of practice. Try to solve as many online CAT mock test/CAT model tests you can and get familiar with the tricks for mensuration.**Consistency in practice:**Students tend to forget the mensuration part that they have done during school times. So key to score good marks in this section is consistency in practice. Spend sufficient time every day practicing quantitative aptitude in general and mensuration in particular for CAT exam. The more you spend time with the problems, the more familiar they will get.**Importance of Formulas:**Learn the mensuration formulas like those for cube, cuboid, cylinder, sphere etc. for CAT as lot of problems can be solved if you have the formula in place. Write the formulas down on a piece of paper and stick it on to the wall where you can see it regularly. It’ll help you to memorize them.**During Exam:**If you get stuck with a mensuration question, don’t waste your time trying to solve it right away. Instead, get on with the others and come back to the question when you are done with the rest of the doable questions.

Suggested Action:

Formulas pertaining to Curved Surface Area, Total Surface Area, Volume for solid figures like:

- Cube,
- Cuboid,
- Cylinder,
- Cone,
- Sphere,
- Frustum
- Polygon,
- Prism,
- Pyramid etc.

- Effect of cavity on the surface area of solid figure,
- Length of longest rod in cubical/cuboid room
- Effect of melting the solids to form new solid
- Slant surface and Whole surface of Pyramid
- Frustum of Pyramid etc.

Mensuration in CAT is one of the easiest topics of Quantitative Aptitude, if you spend enough time preparing for it. Aspirants can always use various shortcuts for solving Mensuration questions; some of useful shortcuts are discussed as under:

**Do take Advantage of SYMMETRY:**In Mensuration many times a question can be solved with the help of SYMMETRY. Questions involving solid figures like cubes, spheres, pyramid etc. can be solved using the concept of SYMMETRY in an easier manner, but for that a good practice and strong analysis is required.**Options Elimination:**There are certain questions where options can be ruled out one by one instead of forming an option. In such questions we just ensure that all the conditions given in the question must be fulfilled and whichever option satisfies all the conditions it will be our answer. But please remember there should not be “None of these” option in such questions.**Previous CAT questions:**Go through all the previous year's CAT Mensuration questions, as so many questions are based on the concepts, which have appeared in earlier CAT exams.**Answering questions in percentage:**So many times, you have a question in which you have to answer the percentage area wasted. In all those cases, you can avoid the actual values given and take the values, which are more suitable for calculation as it would not affect your answer in percentage.

- 1.Remain the same
- 2.Dec. by 13.64%
- 3.Dec. by 15%
- 4.Dec. by 18.75%
- 5.Dec. by 30%

Then, Area of four walls = 2 (l + b) h = 2(3x + 2x) x = 10x2.

Now as Length gets doubled = 6x, Breadth halved = x, Height halved = x/2.

New area of four walls = 2 (6x + x) x/2 = 7x2.

Thus there is a decrease of 30%. Hence, **fifth option is the answer.**

1.27

2.5

3.4

4.9

1. < r

2. = r

3. > r

4. Depends on the height of the cone.

Just try to visualize the three cones from their heads. The central point between the three is definitely at a distance, which is more than the radius; hence **third option is the answer. **Otherwise; just check if you have taken three equal circles who are touching the other two, the circle which will cover those three circles will be definitely the radius of the smaller circle plus something. Now it should be sufficient to conclude that it is more than r.

1. 1: 7 : 56

2. 1: 8 : 64

3. 3: 9 : 18

4. None of these

Suggested Reading :

1. 9/13

2. 11/16

3. 5/16

4. None of these