Question

this que of ncert 11 maths textbook pg no 25 plz answer this que it's urgently i mark u as brainliest​

Answer 1

Question :

A market research group conducted a survey of 1000 consumers and reported that 720 consumers like product A and 450 consumers like product B , what is the least number that must have like both products?

To Find :

• We need to find that how many consumers like both the products n(A ∩ B).

Solution :

⇛Let A be the set of consumers who like product A , and B be the set of consumers who like product B.

› Market research group conducted a survey of 1000 consumers.

Then,

• n(A ∪ B) = 1000

› 720 consumers like product A.

• n(A) = 720

› 450 Consumers like product B .

• n(B) = 450

As we know that,

$\star\underline{ \boxed{ \red{\mathbf {n(A \: \cup \: B) + n(A \: \cap \: B) = n(A) + n(B) }}}}$

➔ n(A ∩ B) = n(A) + n(B) - n(A ∪ B)

➔ n(A ∩ B) = 720 + 450 - 1000

➔ n(A ∩ B) = 1170 - 1000

➔ n(A ∩ B) = 170

Hence,

• 170 consumers like both products A and B.

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