Sets A and B have 3 and 6 elements respectively. What can be the … - Vidyadip

MCQ

Sets $A$ and $B$ have $3$ and $6$ elements respectively. What can be the minimum number of elements in $A \cup B$

A
$3$
✓
$6$
C
$9$
D
$18$

✓

Answer

Correct option: B.

$6$

b
(b) $n(A \cup B) = n(A) + n(B) -n(A \cap B) $ = $3 + 6 - n(A \cap B)$

Since, maximum number of elements in $A \cap B = 3$

$\therefore $ Minimum number of elements in $A \cup B = 9 - 3 = 6$.

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