Common traps to avoid in the Quant section

For most candidates, Quantitative Aptitude is probably the most challenging section to crack in the CAT.  During your preparation, or at least during your full length test-practise stage, you would have developed an idea of what your strongest and weakest areas are (if you haven't, do it at the earliest! It is important to know your strengths as well as your weaknesses.).

The reasons why Quant can be the toughest nut to crack are varied. Most students have a sufficiently good grasp of fundamentals. But, when a challenging question presents itself, they are all at sea. Most students also have a problem with time management. Some would have lost touch with Quant basics after high school. Some don't have the raw speed of formulation and calculation that most “math whizzes” take for granted. Whatever be your tale of woe, remember that that whole point of the CAT preparation exercise is to understand what your weakness is, and work towards improving it.

In the following pages, a few common traps and pitfalls are detailed. Beware of these on the day of the exam. But don't fall into the trap of assuming that these tips have only to be glanced over once before exam day. You may need to go through these in the test practise stage (and possibly even during the preparation stage), so that you can identify and rectify your “favourite” mistake area.

Common pitfalls in the Quant section

1. Problem vs You

The test makers of CAT are experienced in the art of mixing up easy and difficult questions. When you take the CAT, you will find that there are a few absolutely easy questions that you could have solved when you were in 7^th standard. You will also find questions that are extremely tough. This is not done to identify and select the math majors! The reason there is a mixture of questions of varying levels of difficulty is that it reflects real life situations. But, given that you have a deadline, you have to pick and target the lowest hanging fruits.

The CAT will definitely contain difficult problems, and there are good chances that you might start solving them and get stuck somewhere, only to realise eight minutes or so later that you aren't making any headway. So what should you do? Leave it right there and move on to the next question. But what do you do instead? Spend another three minutes just to try to solve the problem and show it who the boss is!

This is probably the most common trap – getting into a literal “fight” with the problem, where solving one problem becomes more important than getting a good sectional score overall. This is a definite way of losing good time that can be employed productively elsewhere.

So how do you avoid this trap? First of all, be aware of it when it happens. When you realise that you have spent more than reasonable time on a question and you are still nowhere close to finding an answer, it is time to consider moving on. How do you know that you are falling into this trap? 

Here are some indicators that might help you decide:

• Your equations begin to get bigger and uglier
• You have filled up half the rough-sheet and have made no real progress
• None of the answer substitution or elimination tricks appears to work
• You go back to reading the question several times
• You see the clock ticking, and you realise that you still haven't even attempted a majority of the section.
• Most of all, you have spent five minutes on this question already and you are still where you started.

What do you do in such a situation? Do you panic and give up? Doing so is going to give you a sense of failure, which will not only affect the rest of your Quant section, but also likely spill over into the Verbal section. At the same time, you can't continue spending time on the same question.

The best way to deal with this situation is to not let it arise in the first place. Make sure that you pick the easy questions first and dispatch them. Then, move on to the marked questions which you think can be solved with some effort. Finally, only when every easy or medium-difficult question is attempted, should you even consider taking up questions from areas you are not comfortable with. 

Remain calm throughout the section.

If you do find yourself in such a situation, identify early when to give up and move on to the next question. Your ego might hurt a bit, but it is definitely not worse than leaving questions unattempted towards the end.

2. Knowing a formula is not the same as Understanding a concept

A lot of students, especially in the later stages of preparation, say that they know all concepts very well, but when it comes to solving problems, they get stuck in the question interpretation or the formulation stage. For example, you “know” what the modulus of a number is. You have read and memorised all the definitions, and you even remember the textbook example well. You also know how to solve each equation type, and yet when you see an equation such as the following one, you get stumped:

|2x – 5| > 2

Now, ask yourself this: If you know all the formulae, theorems and definitions in a particular topic, does it mean that you really “understand” the topic? “Understanding” doesn't mean being able to reproduce or replicate a stated theorem or a solved example. You understand a concept when you are able to visualise it and, and then use your creativity to formulate and obtain a non-mathematical model of something as “dry” as a modulus equation, for example. In this instant case,  |a – b| would mean the distance from the point “a” to the point “b” on the number line. So the distance from the point “2x” and the point “5” is more than 2 units. Or, “2x” is either greater than 7, or less than 3. Aim to achieve a good visual parallel for as many concepts as possible. This not only saves time in solutions, but also gives you clarity of thought.

This is a trap students often fall into. Math problems on the CAT test more than your memory. They test how well you can adapt to situations, and apply simple concepts in complex problems. Be aware of this from an early stage in preparation. Spend more time on the basics. If you have trouble understanding a concept at first, reflect on it till it makes sense. This is more important than solving a dozen questions based just on formula application.

3. Poor time management

Another trap that most test takers fall into is lack of proper time management. Given that there are only 30 questions in a section, and more than two lakh students write the CAT, the difference between an extremely high and a low percentile could be a matter of just one question. You need to make sure that you have at least seen and attempted all the questions in each section, lest you should leave out easy questions towards the end. This calls for a lot of practise. Do as many full length practise tests as possible, and get used to the rigour of a full-length test. You need to sustain your concentration for the entire duration of the test, and you need to have the endurance to finish the test with almost the same energy and alertness as when you started.

Do not leave too many questions to the end. Doing so will only make you more nervous, and you may lose out on some really easy questions.

4. Improper reading of the question

Sometimes you solve an entire question correctly only to find out that you had made a mistake in reading the question. Even though you did everything right, your answer was wrong. Such errors in reading or interpretation show a lack of focus in the early part of solution.

• You may have to slow down while reading the question, and maybe even read it twice to understand it completely. Do not try to save time in this stage!
• Pay special attention to words and phrases in the question whose incorrect interpretation may change the answer drastically. Some examples of such words are:

◦     Distinct, Integer, Positive / Negative / Non-negative, At least / At most, Odds in favour / Odds against, Some / All, And / Or, Not less than / Never greater than

• Also after solving the question, you can verify your answer by re-checking it with the scenario presented in the question. You may not always have time during the test to double-check every solution, but if you have a serious doubt, you can always exercise this option.
• After getting the answer, read the question again because it may ask you to process the solution before arriving at the answer. For example, you may have solved an equation for x, but the question may ask you to find the value of x + 10. Re-read the question to be sure.

6. Silly errors

This is probably the most frustrating of them all. Everything about your solution was correct, except  that you made a silly addition mistake in the final step, and you lost everything because of that. Errors in calculation or solution happen to the best of us, and it is never good when it happens.

Can you improve your accuracy and reduce the number of silly mistakes? Absolutely, yes. Just slow down while solving equations, or be a bit more careful with calculations. Also, practise a lot. Learn the multiplication tables and ratio charts. Do the grind. All that is good enough preparation. But will that help you completely eliminate calculation errors? Unlikely.

Humans are prone to making errors in calculations. You cannot completely eliminate calculation or solution errors. But you can definitely improve your accuracy and reduce the time you take for calculations.

Here is what you can do:

• Find out your strongest and weakest areas. Figure out where you need improvement the most? Is it multiplication tables? Is it quadratic equation solutions?
• Work hard on improving your speed and accuracy in those areas. Keep working on it on a daily basis. You will definitely see an improvement in performance.
• Practise, Practise, Practise.
• On the day of the test, accept that you may still make mistakes. Allow for a margin of error, but be extra careful in areas where you know that you have a proven weakness. If possible, double-check your answers by working backwards from the answer options.

All these things are easier said than done, and it is always easier to rely on hindsight and compile a list than it is to log your errors and rigorously practise on a daily basis. But do remember that whatever your starting point is, you can always, always improve. And whatever be your level of preparation, a bit of caution on the day of the test will definitely pay large dividends.

7.  Build your Eye for detail

Relentlessly train yourself to pick anomalies. If you did not notice, we have jumped from point 4 to point 6 on this list! Every time you let something like this pass you by, make a mental note to look or detail. Just becoming more ‘switched on’ makes a big difference and can be built with practise.

The above article was contributed by Vimal Gopinath, an XIM Bhubaneshwar alumnus who runs 2IIM Bengaluru. The article also features in the CAT Quant book authored by Rajesh Balasubramanian.