Question

if n (a) =20 n (b) = 28, (AVB) =36, then to find out n (a∆b) complete the following activity

pls solve this​

Answer 1

Given:

n(A) = 20

n(B) = 28

n(A∪B) = 36

To find:

Number of elements in (A∩B)

Solution:

Given that,

number of elements in A = 20

Number of elements in B = 28

number of elements in A∪B = 36

We will use the formula,

n(A∪B) = n(A) + n(B) - n(A∩B)

Putting values from the given values

36 = 20 + 28 - n(A∩B)

n(A∩B) = 48 - 36

n(A∩B) = 12

Therefore, number of elements in (A∩B) will be 12.

Answer 2

Answer:

Step-by-step explanation:

Given that,

n ( A ) = 20 ,n ( B ) = 28 and n ( A ∪ B ) = 36

∴ n ( A ∩ B ) = n ( A) + n ( B ) - n ( A ∪ B )

= 20 + 28 - 36

= 48 - 36

= 12 is the answer.