Question

if n(A) =5, n(AUB)=9, n(AΠB) =2,find n(B)=?
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Answer 1

SOLUTION

GIVEN

n(A) = 5 , n( A ∪ B) = 9 , n( A ∩ B) = 2

TO DETERMINE

The value of n(B)

EVALUATION

Here it is given that

n(A) = 5 , n( A ∪ B) = 9 , n( A ∩ B) = 2

Now we know that

n( A ∪ B) = n(A) + n(B) - n( A ∩ B)

⇒ 9 = 5 + n(B) - 2

⇒ n(B) = 9 - 5 + 2

⇒ n(B) = 6

FINAL ANSWER

n(B) = 6

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Answer 2

Answer:

The value of n(B) is $6$

Step-by-step explanation:

Given

n(A)$=5$

n(A∪B)=$9$

n(A∩B)=$2$

We need to find the value of n(B)

We know the formula as

n(A∪B)=n(A)+n(B)-n(A∩B)

We get as

$9=5+x-2\\\\x=6$