Restate the stem as follows:
Is the unknown number one of 12 15 18 21 24 27 30 33 36 39 42 45 48 ???
stmt 1 to : (X+Y)/18= Integer
stmt 2 to: XY/9= Integer
Consider stmt one alone: The digits in none of the listed numbers add up to a number divisible by 18. Sum of digits of 48 and 39 both yield 12, which is too low. So the answer to the stem is definitely NO. Suff
Consider stmt two alone: 36 is divisible by 9 (Yes to the stem) and also 90 is divisible by 9 (No to the stem) => Insuf
Guys, don't bother with 0. I don't think that in such questions regarding digits and digit place, we can consider one digit -ive and another +ve. Do we have a SINGLE number such as 1-2 or 4-5 (Don't read it minus: It's a negative two-digit number with the sign before the second digit)?
If you consider 0, you can make, e.g., -99, but since the question doesn't determine the order of digits, then you have to also accept existence of 9-9
If you are still reluctant, ok, maybe we can consider -ive or +ive in such question, too, but even then you have to write the positive number like 10X+Y and -ive number like -(10X+Y)
. Even in this case your -99 and 99 are in fact the same number b/c the -ive sign is irrelevant to our discussion of what X and Y are. What counts is that X and y are both 9 in both numbers, so they are the same numbers actually.
Am I clear or just lost in my faulty reasoning?
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