Question: Odd or Prime

Comment on Odd or Prime

Great explanation and I totally understand. My logic to solve this question instantly was by realizing that there an infinite number of positive integers therefore it is impossible to determine the answer. For example the 5 integers could be [1,2,3,4,5] or [43, 127, 4,356, 94,359, 104,506].

Is there anything wrong with that logic?
greenlight-admin's picture

That's a great idea, TEV.
Unfortunately, just because a certain scenario may have infinitely many possibilities, we can't then conclude that the correct answer is D.

For example, consider this rudimentary example question:

Given: x is a prime number
QUANTITY A: x
QUANTITY B: 0

In this case, x can have infinitely many values (e.g., 2, 3, 5, 7, 11, 13, 17, 19, 23, ... etc)
However, since all prime numbers are POSITIVE, we can be certain that Quantity A is greater than Quantity B.
So, here the correct answer is A
---------------------

Now consider this question:

Given: x is a prime number
QUANTITY A: x
QUANTITY B: 10

Once again, x can have infinitely many values.
However, in this case, we can test some values to show that the correct answer is D.

For example, x can equal 3, in which case, Quantity B is greater than Quantity A.
Alternatively, x can equal 17, in which case, Quantity A is greater than Quantity B.

So, here the correct answer is D

Does that help?

Cheers,
Brent

That does help. Thanks for the detailed explanation.

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