Update

Muft Shiksha™ एक 100% Free Education Portal है 🇮🇳, जिसका उद्देश्य Class 9–12 के हर विद्यार्थी तक High-Quality Education को पूरी तरह मुफ्त पहुँचाना है। 🇮🇳 हम मानते हैं कि अच्छी शिक्षा किसी student की आर्थिक स्थिति पर निर्भर नहीं होनी चाहिए। 🇮🇳 हर विद्यार्थी को वही Quality Study Material, MCQs, Quizzes, Exam Preparation, Concept-Based Learning और Bilingual Support मिलना चाहिए, जो आमतौर पर महंगी Coaching या Premium Platforms में मिलता है। Muft Shiksha™ 🇮🇳 इसी सोच के साथ बनाया गया है

Subjects

If n(U) = 110, n(A) = 58, n(B) = 47, and n(A ∩ B) = 20, what is n((A ∪ B)′)?

Advertisement

Answer and explanation

Correct answer: 25

First calculate the size of the union using n(A ∪ B) = n(A) + n(B) − n(A ∩ B). Hence n(A ∪ B) = 58 + 47 − 20 = 85. The complement of the union contains all elements of the universal set that are outside both A and B. Therefore n((A ∪ B)′) = n(U) − n(A ∪ B) = 110 − 85 = 25. Thus option A is correct.

Tags

setsvenn-diagramsunioncomplementComplement of a Set and Its PropertiesMathematicsClass 10 MCQ

Frequently asked questions

What is the correct answer to this question?

25

Why is this the correct answer?

First calculate the size of the union using n(A ∪ B) = n(A) + n(B) − n(A ∩ B). Hence n(A ∪ B) = 58 + 47 − 20 = 85. The complement of the union contains all elements of the universal set that are outside both A and B. Therefore n((A ∪ B)′) = n(U) − n(A ∪ B) = 110 − 85 = 25. Thus option A is correct.

Which subject and chapter does this question cover?

This is a Class 10 Mathematics question. Chapter: Sets. Topic: Complement of a Set and Its Properties.

Advertisement