Discussion Problem_ (7)

[duck]

Let A,B,C and D be finite sets such that |A| < |C| and |B| = |D|, where |A| stands for the number of elements in the set A. Then
(a) |A⋃B|<|C⋃D|
(b) |A⋃B|≤|C⋃D|but|A⋃B|<|C⋃D| need not always be true.
(c) |A⋃B|<2|C⋃D|but|A⋃B|≤|C⋃D| need not always be true.
(d) none of the foregoing statements is true.

[Mauli]

i am getting c as the answer.
i thought about it intuitively.
is their a formal way to approach. ?
 in the first place.. am i correct?

[ss]

I think the answer should be c..
option a and b can be eliminated using the following examples
A=(1,2)
B=(4,5,6)
C=(1,2,3)
D=(2,3,4)
No of elements in A union B = 5
No of C union D = 4

[duck]

Hi.. :)

Well done!
Correct Answer (c)