Deductive reasoning- concepts and problems

Sample problems

Question-1 

A-All cricket players are fit and healthy.

B-All famous sportspeople are cricketers.

C-All famous sportspeople are fit and healthy.

If statements A, B are true, then tell if the C is true or not?

Answer- C is true.

Question-2 

A- In our seventh standard this year, 90% of students achieved 7 to 10 CGPA.

B- Last year, 92% of students achieved 7 to 10 CGPA.

C- The school thinks that the new approach had a brilliant impact on the performance of students.

If statements A, B are true, then tell if the C is true or not?

Answer- C is false.

Question-3 

A- Khali is stronger than John Cena

B- But John Cena is stronger than The Rock.

C- The Rock is stronger than Khali.

If statements A, B are true, then tell if the C is true or not?

Answer- C is false. 

Eight people are sitting around a dinner table facing inwards.

G is two seats to A’s left.

B is three seats to G’s right.

E is two seats to G’s left.

F is six seats to H’s right.

D is six seats to F’s right.

C is not sitting next to G.

Who sits one seat to D’s left?

(a) C

(b) F

(c) G

(d) H

Answer- (a) C.

Explanation- let’s see the representation of each step-

1-

2-

3-

4-

5-

Thus the person on one seat to D’s left is C.

Frequently Asked Questions

1. What is deductive reasoning?
   It is a logical process in which we draw conclusions based on a few rules established by us.
    
2. How to solve arrangement problems in deductive reasoning?
   To solve the arrangements problems based on deductive reasoning, you should start with representing each statement in a graphical form. Finally, you will have the arrangement of objects in the given order. Then you can answer the asked questions.
    
3. What are syllogisms?
   It is a type of deductive reasoning in which we lay out a few rules or premises and then conclude based on them. 
    
4. How is inductive reasoning different from deductive reasoning?
   Inductive reasoning is based on using observations to lay out rules or set up premises. In the case of deductive reasoning, we draw out specific conclusions based on the predefined rules/premises.
    
5. What are the types of deductive reasoning?
   Based on the premises and conclusions, deductive reasoning is generally divided into three categories-
   Syllogisms
   Modus ponens
   Modus tollens

Key Takeaways

In this blog, we learned about deductive reasoning, which is an important topic for aptitude rounds of any exams. 

We started with learning about the types of deductive reasoning then the types of problems generally asked around it. Then we practiced the discussed concepts with the help of some examples.

You can learn more important topics for aptitude exams here and practice similar problems on Code studio.