Table of contents |
|
What is Binary Logic? |
|
Concepts Required to Solve Binary Logic Problems |
|
Binary Logic Question Types |
|
Step Wise Solved Examples |
|
The logical Reasoning section in the Common Admission Test (CAT) carries a couple of questions on binary logic. The application of this logic is more in finding out the truthfulness of the statements made.
Each question contains two logic streams that have to be matched, in order to get the correct answer.
The Binary logic derives its name from the Boolean logic which is the synonym to two-value logic system. In fact, it is the sub area of algebra called Boolean algebra in which the values of the variables are the truth values - true and false.
In these types of problems: we have people who either speak a true statement or a false statement. Hence these people are divided into three categories:
1. TruthTeller: This person will always speak the truth. All the statements made by this person are true.
2. Liar: This person will always tell a lie. All statements made by this person are false.
3. Alternators: This person always alternates between the truth and the lie.
Binary logic questions are all about making some assumptions. These assumptions may give rise to some contradictions which are the indicators that our assumptions are wrong. If for any assumption we do not get even a single contradiction, then that is the solution for the given problem.
Three persons speak two statements each - one of which is true, the other is false.
The two logic streams to be considered are:
Two types of persons are found in this type of question.
If a person always speaks the truth, then whatever statement he says must be true. However, a clash might be there if it can be seen that the statement is obviously false.
Q: Booker says," At least one person among Shane and I always lie." What types are Booker and Shane respectively?
Example 1: Three boys- Aman, Bagheer, and Chiru replied to the question, “Who among you is a Doctor” in the following manner:
We know exactly one of these boys is a Doctor, one is a Painter and one is an Athlete.
Further, one always speaks the truth, one always lies, and one alternates between the truth and the lie.
![]() |
Download the notes
Introduction & Examples: Binary Logic
|
Download as PDF |
With the help of some statements made by these people, we might be able to identify them without any assumption. Here is a list of 4 statements that one must always look out for to make the task easier. If any one of these is made by any person, then we can categorize them as explained below.
1. I am a liar
2. I am not a truth-teller
3. I am an alternator
4. I am not an alternator
So the answer to the question, ‘Who is a Doctor’, is Chiru.
Other statements such as, “I am a truth-teller”, can be made by all the three categories of person and so will not be of much help to us.
Step 2
Example 2: Utkarsh, Ravi, and Shivam made the following statements regarding the type of vehicle they own. Each one of them belongs to exactly one category of truth-teller, liar or alternator. Only one among them is a truth-teller. Further, we know each of them own a different vehicle and each of them own exactly one among car, cycle and bike.
Solution:
Directions for examples 3 & 4: Read the following paragraph and answer the questions that follow.
There are two types of inhabitants in Tatabalery- A type & B type. The A type of inhabitants always speak the truth and the B Type of inhabitants always lie.
Example 3: Rocky says, " I always lie." which type of inhabitant is he?
(a) A
(b) B
(c) EitherA or B
(d) The given statement is infeasible
Answer: (d)
Example 4: Peter says," According to Rocky, I always speak the truth." Which of the following is a correct conclusion?
(a) Peter has to be of type A
(b) Peter has to be of type B
(c) Rocky has to be of type A
(d) Rocky has to be of type B
Answer: (c)
92 videos|123 docs|94 tests
|
1. What is binary logic? | ![]() |
2. What are the concepts required to solve binary logic problems? | ![]() |
3. What are the different types of binary logic questions? | ![]() |
4. Can you provide an example of solving a binary logic problem step by step? | ![]() |
5. How is binary logic used in computer programming? | ![]() |