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Re: The Ultimate Q51 Guide [Expert Level]
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18 May 2016, 15:35
(ex 2) A, B are two sets whose elements are integers, A∪B represent union set of two sets A, B. Is each of the elements in the set A divisible by 3?
1) A∪B={13,17,31,47,52}
2) B={13,17,47}
Also, questions involving the Common Mistake Type 4(A) is very tricky.
(ex 2) A, B are two sets whose elements are integers, A∪B represent union set of two sets A, B. Is each of the elements in the set A divisible by 3?
1) A∪B={13,17,31,47,52}
2) B={13,17,47}
Answer: A
There are questions that involve both the common mistake type 1 (no is also an answer) and the common mistake type 4(A). In above question, C is also an answer. If we look at that condition 1), even if A’s elements are any numbers, it cannot be divided by 3. The answer is no and the condition is sufficient. Therefore, the correct answer is A.
This is a type of questions that appears in 50-51.