Explore topic-wise MCQs in Discrete Mathematics.

This section includes 107 Mcqs, each offering curated multiple-choice questions to sharpen your Discrete Mathematics knowledge and support exam preparation. Choose a topic below to get started.

51.

Determine the truth value of statement ∃n (4n = 3n) if the domain consists of all integers.

A. True
B. False
C. May be True or False
D. Can't say
Answer» B. False
52.

p ∨ q is logically equivalent to ________

A. ¬q → ¬p
B. q → p
C. ¬p → ¬q
D. ¬p → q
Answer» E.
53.

Let Q(x) be the statement “x < 5.” What is the truth value of the quantification ∀xQ(x), having domains as real numbers.

A. True
B. False
C. May be True or False
D. Can't say
Answer» C. May be True or False
54.

p → q is logically equivalent to ________

A. ¬p ∨ ¬q
B. p ∨ ¬q
C. ¬p ∨ q
D. ¬p ∧ q
Answer» D. ¬p ∧ q
55.

p ∧ q is logically equivalent to ________

A. ¬ (p → ¬q)
B. (p → ¬q)
C. (¬p → ¬q)
D. (¬p → q)
Answer» B. (p → ¬q)
56.

¬ (p ↔ q) is logically equivalent to ________

A. q↔p
B. p↔¬q
C. ¬p↔¬q
D. ¬q↔¬p
Answer» C. ¬p↔¬q
57.

p ↔ q is logically equivalent to ________

A. (p → q) → (q → p)
B. (p → q) ∨ (q → p)
C. (p → q) ∧ (q → p)
D. (p ∧ q) → (q ∧ p)
Answer» D. (p ∧ q) → (q ∧ p)
58.

(p → r) ∨ (q → r) is logically equivalent to ________

A. (p ∧ q) ∨ r
B. (p ∨ q) → r
C. (p ∧ q) → r
D. (p → q) → r
Answer» D. (p → q) → r
59.

If A is “001100” and B is “010101” then what is the value of A (Ex-or) B?

A. 000000
B. 111111
C. 001101
D. 011001
Answer» E.
60.

Let P (x) denote the statement “x >7.” Which of these have truth value true?

A. P (0)
B. P (4)
C. P (6)
D. P (9)
Answer» E.
61.

(p → q) ∧ (p → r) is logically equivalent to ________

A. p → (q ∧ r)
B. p → (q ∨ r)
C. p ∧ (q ∨ r)
D. p ∨ (q ∧ r)
Answer» B. p → (q ∨ r)
62.

If a bit string contains {0, 1} only, having length 5 has no more than 2 ones in it. Then how many such bit strings are possible?

A. 14
B. 12
C. 15
D. 16
Answer» E.
63.

The Ex-nor of this string “01010101” with “11111111” is?

A. 10101010
B. 00110100
C. 01010101
D. 10101001
Answer» D. 10101001
64.

What is the one’s complement of this string “01010100”?

A. 10101010
B. 00110101
C. 10101011
D. 10101001
Answer» D. 10101001
65.

If in a bits string of {0,1}, of length 4, such that no two ones are together. Then the total number of such possible strings are?

A. 1
B. 5
C. 7
D. 4
Answer» D. 4
66.

What is the 2’s complement of this string “01010100”?

A. 10101010
B. 00110100
C. 10101100
D. 10101001
Answer» D. 10101001
67.

Let P and Q be statements, then P<->Q is logically equivalent to __________

A. P<->~Q
B. ~P<->Q
C. ~P<->~Q
D. None of the mentioned
Answer» D. None of the mentioned
68.

Let A: “010101”, B=?, If { A (Ex-or) B } is a resultant string of all ones then which of the following statement regarding B is correct?

A. B is negation of A
B. B is 101010
C. {A (and) B} is a resultant string having all zeroes
D. All of the mentioned
Answer» E.
69.

The compound statement A-> (A->B) is false, then the truth values of A, B are respectively _________

A. T, T
B. F, T
C. T, F
D. F, F
Answer» D. F, F
70.

How many bits string of length 4 are possible such that they contain 2 ones and 2 zeroes?

A. 4
B. 2
C. 5
D. 6
Answer» E.
71.

Which of the following bits is the negation of the bits “010110”?

A. 111001
B. 001001
C. 101001
D. 111111
Answer» D. 111111
72.

Let P: We should be honest., Q: We should be dedicated., R: We should be overconfident. Then ‘We should be honest or dedicated but not overconfident.’ is best represented by?

A. ~P V ~Q V R
B. P ∧ ~Q ∧ R
C. P V Q ∧ R
D. P V Q ∧ ~R
Answer» E.
73.

Which of the following option is suitable, if A is “10110110”, B is”11100000” and C is”10100000”?

A. C=A or B
B. C=~A
C. C=~B
D. C=A and B
Answer» E.
74.

Let P: I am in Bangalore.; Q: I love cricket.; then q -> p(q implies p) is?

A. If I love cricket then I am in Bangalore
B. If I am in Bangalore then I love cricket
C. I am not in Bangalore
D. I love cricket
Answer» B. If I am in Bangalore then I love cricket
75.

What is the value of x after this statement, assuming the initial value of x is 5?

A. 1
B. 3
C. 0
D. 2
Answer» D. 2
76.

The truth value ‘9 is prime then 3 is even’.

A. True
B. False
C. May be True or False
D. Can't say
Answer» B. False
77.

Let P: I am in Delhi.; Q: Delhi is clean.; then q ^ p(q and p) is?

A. Delhi is clean and I am in Delhi
B. Delhi is not clean or I am in Delhi
C. I am in Delhi and Delhi is not clean
D. Delhi is clean but I am in Mumbai
Answer» B. Delhi is not clean or I am in Delhi
78.

Let P: This is a great website, Q: You should not come back here. Then ‘This is a great website and you should come back here.’ is best represented by?

A. ~P V ~Q
B. P ∧ ~Q
C. P V Q
D. P ∧ Q
Answer» C. P V Q
79.

Let P: If Sahil bowls, Saurabh hits a century.; Q: If Raju bowls, Sahil gets out on first ball. Now if P is true and Q is false then which of the following can be true?

A. Raju bowled and Sahil got out on first ball
B. Raju did not bowled
C. Sahil bowled and Saurabh hits a century
D. Sahil bowled and Saurabh got out
Answer» D. Sahil bowled and Saurabh got out
80.

Which of the following represents: ~A (negation of A) if A stands for “I like badminton but hate maths”?

A. I hate badminton and maths
B. I do not like badminton or maths
C. I dislike badminton but love maths
D. I hate badminton or like maths
Answer» E.
81.

Which of the following statements is the negation of the statements “4 is odd or -9 is positive”?

A. 4 is even or -9 is not negative
B. 4 is odd or -9 is not negative
C. 4 is even and -9 is negative
D. 4 is odd and -9 is not negative
Answer» D. 4 is odd and -9 is not negative
82.

The compound statement A v ~(A ∧ B).

A. True
B. False
C. May be True or False
D. Can't say
Answer» B. False
83.

Which of the following is De-Morgan’s law?

A. P ∧ (Q v R) Ξ (P ∧ Q) v (P ∧ R)
B. ~(P ∧ R) Ξ ~P v ~R, ~(P v R) Ξ ~P ∧ ~R
C. P v ~P Ξ True, P ∧ ~P Ξ False
D. None of the mentioned
Answer» C. P v ~P Ξ True, P ∧ ~P Ξ False
84.

~ A v ~ B is logically equivalent to?

A. ~ A → ~ B
B. ~ A ∧ ~ B
C. A → ~B
D. B V A
Answer» D. B V A
85.

What is the dual of (A ∧ B) v (C ∧ D)?

A. (A V B) v (C v D)
B. (A V B) ^ (C v D)
C. (A V B) v (C ∧ D)
D. (A ∧ B) v (C v D)
Answer» C. (A V B) v (C ∧ D)
86.

Which of the following satisfies commutative law?

A.
B. v
C.
D. All of the mentioned
Answer» E.
87.

Negation of statement (A ∧ B) → (B ∧ C) is _____________

A. (A ∧ B) →(~B ∧ ~C)
B. ~(A ∧ B) v ( B v C)
C. ~(A →B) →(~B ∧ C)
D. None of the mentioned
Answer» B. ~(A ∧ B) v ( B v C)
88.

If P is always against the testimony of Q, then the compound statement P→(P v ~Q) is a __________

A. Tautology
B. Contradiction
C. Contingency
D. None of the mentioned
Answer» B. Contradiction
89.

If the truth value of A v B is true, then truth value of ~A ∧ B can be ___________

A. True if A is false
B. False if A is false
C. False if B is true and A is false
D. None of the mentioned
Answer» B. False if A is false
90.

The statement which is logically equivalent to A∧ (and) B is?

A. A->B
B. ~A ∧ ~ B
C. A ∧ ~B
D. ~(A->~B)
Answer» E.
91.

Let P, Q, R be true, false true, respectively, which of the following is true?

A. P∧Q∧R
B. P∧~Q∧~R
C. Q->(P∧R)
D. P->(Q∧R)
Answer» D. P->(Q∧R)
92.

If in a for it to be complete it is necessary for switch A to be closed and either of switch B or C to be closed, then which can be true?

A. Switch A should in parallel with B and C is series to them
B. Switch A should be in series with a parallel circuit of B and C
C. All of the mentioned
D. None of the mentioned
Answer» C. All of the mentioned
93.

If there are ‘M’ switches in parallel numbered from 1, 2, …, M. For circuit to be complete and bulb to glow which of the following is necessary

A. 1∧ 2∧ 3 ∧ … ∧M should be on
B. 1∧ 2∧ 3 ∧ … ∧M should be off
C. 1 v 2 v 3 v … v M should be on
D. None of the mentioned
Answer» D. None of the mentioned
94.

Consider the following statements.

A. A->B->C
B. B∧(C->A)
C. C->B∧A
D. B<->A∧C
Answer» C. C->B∧A
95.

Let P, Q, R be true, false, false, respectively, which of the following is true?

A. P∧(Q∧~R)
B. (P->Q)∧~R
C. Q<->(P∧R)
D. P<->(QvR)
Answer» D. P<->(QvR)
96.

“Match will be played only if it is not a humid day.” The negation of this statement is?

A. Match will be played but it is a humid day
B. Match will be played or it is a humid day
C. All of the mentioned statement are correct
D. None of the mentioned
Answer» B. Match will be played or it is a humid day
97.

The statement (~P<->Q)∧~Q is true when?

A. P: True Q: False
B. P: True Q: True
C. P: False Q: True
D. P: False Q: False
Answer» B. P: True Q: True
98.

If there are ‘M’ switches in series numbered from 1, 2, …, M. For circuit to be complete and bulb to glow which of the following is necessary?

A. 1∧ 2∧ 3 ∧ … ∧M should be on
B. 1∧ 2∧ 3 ∧ … ∧M should be off
C. 1 v 2 v 3 v … v M should be on
D. None of the mentioned
Answer» B. 1∧ 2∧ 3 ∧ … ∧M should be off
99.

In the circuit shown the lamp will be glowing if _________

A. P: True, Q: False
B. P: True, Q: True
C. P: False, Q: False
D. None of the mentioned
Answer» B. P: True, Q: True
100.

The truth value of ‘4+3=7 or 5 is not prime’.

A. True
B. False
C. May be True or False
D. Can't say
Answer» B. False