If A = {4, 7, 10, 13, 17} and B = {3, 5, 7, 9}, then which of the following statements is true?

This is a multiple choice question and the answers are:

A ∪ B = {7}

B ⊆ B

B ⊂ A

Only answer if your 100% sure, so no guessing please 🙂

The second choice is the correct one.

Specifically, the first answer is wrong because the union of sets A and B would be {3, 4, 5, 7, 9, 10, 13, 17}.

The third answer is wrong because B is not a subset of A – there are elements in B that are not also in A.

The second answer is, in fact, true by default, because for *any* set B, B ⊆ B (in other words, every set is its own subset).

Hope that helps!
second one is always true. A set is always its own subset.

just for sanity’s sake…

first one is false: the union of A and B is not {7}

third one is false: B is not a subset of A because A does not contain 3,5, and 9.
This question is impossible to answer without guessing because your multuple choices are unclear.

But if choice one is A intersect B, then that choice is correct.
A âª B = {7} is false

B â A is false

B â B is always true
A U B is not equal to {7} so, FALSE

B is a subset os B, so TRUE

B is not a subset of A, so FALSE
The middle one is the answer.

B is included and equal to B.