CAT 2001DILR Question 43

2 SetsEasy
Passage / Data

Answer the following question based on the information given below.

A and B are two sets (e.g. A = mothers, B = women). The elements that could belong to both the sets (e.g. women who are mothers) is given by the set C = A.B. The elements which could belong to either A or B, or both, is indicated by the set D = A ∪ B. A set that does not contain any elements is known as a null set, represented by ϕ (for example, if none of the women in the set B is a mother, they C = A.B is a null set, or C = ϕ).

Let 'V' signify the set of all vertebrates; 'M' the set of all mammals; 'D' dogs; 'F' fish; 'A' Alsatian and 'P', a dog named Pluto.

If P.A = ϕ and P ∪ A = D, then which of the following is true?

Answer & solution

  • A

    Pluto and Alsatians are dogs.

  • B

    Pluto is an Alsatian.

  • Pluto is not an Alsatian.

  • D

    D is a null set.

Solution

P. A = ϕ means that "Pluto is not an Alsatian".

Hence, option (c).

CAT 2001 DILR Q43: If P.A = ϕ and P ∪ A = D, then which of the following is true? — Solution | TheCATExam