Top 150+ Solved Discrete Structure (DS) MCQ Questions Answer
Q. ……… is an unordered collection of elements where an element can occur as a member more than once
a. Multiset
b. ordered set
c. set
d. None
Q. If U = {1, 2, 3, . . . 10 } and S = { 4, 5, 6, 7, 8 }, then S ' =
a. { 9, 10 }
b. {1, 2, 3 }
c. {1, 2, 3 9 }
d. {1, 2, 3 9 10 }
Q. If U = {1, 2, 3, . . . 20 } and S = set of prime numbers , then S =
a. { 3, 5, 7, 11, 13,17 }
b. { 2, 3, 5, 7, 11,13, 17, 19 }
c. {1, 3, 5, 7, 9,11, 13, 15,17, 19 }
d. {1, 2, 3, 5, 7,11, 13, 17 }
Q. Consider the statement,“If n is divisible by 30 then n is divisible by 2 and by 3 andby 5.”Which of the following statements is equivalent to this statement?
a. If n is not divisible by 30 then n is divisible by 2 or divisible by 3 or divisibleby 5
b. If n is not divisible by 30 then n is not divisible by 2 or not divisible by 3 or not divisible by 5
c. If n is divisible by 2 and divisible by 3 anddivisible by 5 then n is divisible by 30.
d. If n is not divisible by 2 or not divisible by 3 or not divisible by 5 then n is not divisible by 30
Q. Which of the following statements is the contrapositive of the statement, “You win thegame if you know the rules but are not overconfident.”
a. If you lose the game then you don’t know the rules or you are overconfident.
b. A sufficient condition that you win the game is that you know the rules or you are not over confident
c. If you don’t know the rules or are overconfident you lose the game.
d. If you know the rules and are overconfiden t then you win the game.
Q. A sufficient condition that a triangle T be a right triangle is that a2 + b2 = c2. An equivalent statement is
a. If T is a right triangle then a2 + b2 = c2.
b. If a2 + b2 = c2 then T is a right triangle.
c. If a2 + b2 6= c2 then T is not a right triangle.
d. T is a right triangle only if a2 + b2 = c2.
Q. Which of the following is the inverse of the statement: " If I eat a mango than I do not drink milk".
a. I drink milk only if I do not eat a mango
b. If I don’t eat a mango then I drink milk
c. If I do not drink milk then I eat mango
d. None
Q. which of the following is the contrapositive of the statement: " A quadrilateral is a square only if it is both rectangle and a rhombus".
a. If a rectangle is not a a rhombus it is not a square
b. If a rhombus is not rectangle it is not a square
c. If a quadrilateral is neither a rectangle nor a rhombus then it is not a square
d. None
Q. For a conditional statement p===>q, which of the following is incorrect.
a. Converse of the inverse is its contrapositive
b. contrapositive of the converse is its inverse
c. Inverse of thecontrapositiv e is its converse
d. None
Q. the truth table for exclusive disjunction will be
a. tautology
b. Contradiction
c. Logical equivalent
d. p or q but not both