You probably know that guessing is a good idea on the IELTS- unlike other standardized tests, there is no penalty for getting a wrong answer. Even if you have no idea about a question, you still have a 20-25% chance of getting it right. Most students do not understand the impact that proper guessing can have on their score. Unless you score extremely high, guessing will significantly contribute to your final score.

Monkeys Take the IELTS
What most students don’t realize is that to insure that 20-25% chance, you have to guess randomly. If you put 20 monkeys in a room to take the IELTS, assuming they answered once per question and behaved themselves, on average they would get 20-25% of the questions correct on a five choice multiple choice problem. Put 20 students in the room, and the average will be much lower among guessed questions. Why?
IELTS intentionally writes deceptive answer choices that 'look' right. A student has no idea about a question, so picks the “best looking” answer, which is often wrong. The monkey has no idea what looks good and what doesn’t, so will consistently be lucky about 20-25% of the time.
Students will eliminate answer choices from the guessing pool based on a hunch or intuition. Simple but correct answers often get excluded, leaving a 0% chance of being correct. The monkey has no clue, and often gets lucky with the best choice.
This is why the process of elimination endorsed by most test courses is flawed and detrimental to your performance. students don’t guess, they make an ignorant stab in the dark that is usually worse than random.

Let me introduce one of the most valuable ideas of this course. the $5 challenge:

You only mark your 'best guess' if you are willing to bet $5 on it.
You only eliminate choices from guessing if you are willing to bet $5 on it.

Why $5? Five dollars is an amount of money that is small yet not insignificant, and can really add up fast (20 questions could cost you $100). Likewise, each answer choice on one question of the IELTS will have a small impact on your overall score, but it can really add up to a lot of points in the end.

The process of elimination IS valuable. The following shows your chance of guessing it right:
If you eliminate this many choices on a 3 choice multiple choice problem: 0 1 2
Chance of getting it correct 33% 50% 100%
However, if you accidentally eliminate the right answer or go on a hunch for an incorrect answer, your chances drop dramatically: to 0%. By guessing among all the answer choices, you are GUARANTEED to have a shot at the right answer.

That’s why the $5 test is so valuable. if you give up the advantage and safety of a pure guess, it had better be worth the risk.

What we still haven’t covered is how to be sure that whatever guess you make is truly random. Here’s the easiest way:

Always pick the first answer choice among those remaining.

Such a technique means that you have decided, before you see a single test question, exactly how you are going to guess and since the order of choices tells you nothing about which one is correct, this guessing technique is perfectly random.

Let’s try an example:

A student encounters the following problem on the Listening Module in a conversation about the chemical term 'amine', a derivative of ammonia:

In the reaction, the amine will be?
neutralized
protonated
deprotonated
The student has a small idea about this question- he is pretty sure that the amine will be deprotonated, but he wouldn’t bet $5 on it. He knows that the amine is either protonated or deprotoned, so he is willing to bet $5 on choice A not being correct. Now he is down to B and C. At this point, he guesses B, since B is the first choice remaining.

The student is correct by choosing B, since the amine will be protonated. He only eliminated those choices he was willing to bet money on, AND he did not let his stale memories (often things not known definitely will get mixed up in the exact opposite arrangement in one’s head) about protonation and deprotonation influence his guess. He blindly chose the first remaining choice, and was rewarded with the fruits of a random guess.

This section is not meant to scare you away from making educated guesses or eliminating choices- you just need to define when a choice is worth eliminating. The $5 test, along with a pre-defined random guessing strategy, is the best way to make sure you reap all of the benefits of guessing.

Slang
Scientific sounding answers are better than slang ones. In the answer choices below, choice B is much less scientific and is incorrect, while choice A is a
scientific analytical choice and is correct.

Example:
To compare the outcomes of the two different kinds of treatment.
Because some subjects insisted on getting one or the other of the treatments.
Extreme Statements
Avoid wild answers that throw out highly controversial ideas that are proclaimed as established fact. Choice A is a radical idea and is incorrect. Choice B is a calm rational statement. Notice that Choice B does not make a definitive, uncompromising stance, using a hedge word 'if' to provide wiggle room.

Example:
Bypass surgery should be discontinued completely.
Medication should be used instead of surgery for patients who have not had a heart attack if they suffer from mild chest pain and mild coronary artery blockage.
Similar Answer Choices
When you have two answer choices that are direct opposites, one of them is usually the correct answer. Example:
described the author’s reasoning about the influence of his childhood on his adult life.
described the author’s reasoning about the influence of his parents on his adult life.
These two answer choices are very similar and fall into the same family of answer choices. A family of answer choices is when two or three answer choices are very similar. Often two will be opposites and one may show an equality.

Example:
Plan I or Plan II can be conducted at equal cost
Plan I would be less expensive than Plan II
Plan II would be less expensive than Plan I
Neither Plan I nor Plan II would be effective
Note how the first three choices are all related. They all ask about a cost comparison. Beware of immediately recognizing choices B and C as opposites and choosing one of those two. Choice A is in the same family of questions and should be considered as well. However, choice D is not in the same family of questions. It has nothing to do with cost and can be discounted in most cases.

Hedging
When asked for a conclusion that may be drawn, look for critical 'hedge' phrases, such as likely, may, can, will often, sometimes, etc, often, almost, mostly, usually, generally, rarely, sometimes. Question writers insert these hedge phrases to cover every possibility. Often an answer will be wrong simply because it leaves no room for exception. Avoid answer choices that have definitive words like 'exactly', and 'always'.

Summary of Guessing Techniques
Eliminate as many choices as you can by using the $5 test. Use the common guessing strategies to help in the elimination process, but only eliminate choices that pass the $5 test.
Among the remaining choices, only pick your 'best guess' if it passes the $5 test.
Otherwise, guess randomly by picking the first remaining choice.