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X and Y are integers, X is even and negative, Y is odd and positive. W
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22 Jun 2016, 03:04
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53% (01:48) correct 47% (01:38) wrong based on 184 sessions
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X and Y are integers, X is even and negative, Y is odd and positive. Which of the following could be false? 1. (X + Y) is an odd number. 2. Y^(X + Y) is an integer. 3. X^Y is a positive number. A. 2 only. B. 3 only. C. 1 and 3 only. D. 2 and 3 only. E. 1, 2 and 3.
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Re: X and Y are integers, X is even and negative, Y is odd and positive. W
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22 Jun 2016, 04:26
Answer is B : 3 only,
Using the properties for even and odd numbers along with positive and negatives,
1. (X + Y) is an odd number : even + odd is always a odd number, so eliminate 1 2. Y^(X + Y) is an integer. : an odd and positive number could be raised to power of either positive or negative, so not conclusive, elimiate 2 3. X^Y is a positive number. : a negative number raised to power of odd number is always negative.
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Re: X and Y are integers, X is even and negative, Y is odd and positive. W
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22 Jun 2016, 04:59
Bunuel wrote: X and Y are integers, X is even and negative, Y is odd and positive. Which of the following could be false?
1. (X + Y) is an odd number. 2. Y^(X + Y) is an integer. 3. X^Y is a positive number.
A. 2 only. B. 3 only. C. 1 and 3 only. D. 2 and 3 only. E. 1, 2 and 3. 1. (X + Y) is an odd number. even+odd= odd. True2. Y^(X + Y) is an integer. odd ^(even+odd)= odd ^odd= odd integer. True3. X^Y is a positive number.. ve even ^+ve odd= ve integer (odd power means the number will retain its sign). Not true.B is the answer
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Re: X and Y are integers, X is even and negative, Y is odd and positive. W
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22 Jun 2016, 05:08
Bunuel wrote: X and Y are integers, X is even and negative, Y is odd and positive. Which of the following could be false?
1. (X + Y) is an odd number. 2. Y^(X + Y) is an integer. 3. X^Y is a positive number.
A. 2 only. B. 3 only. C. 1 and 3 only. D. 2 and 3 only. E. 1, 2 and 3. X is even and Y is odd. X+Y will always be odd. This will never be false. so C and E are out of contention. Now X^Y. X = (2) Y = 3 This will always be negative. So (3) is always False. A is out. We will have to check (2) Y^(X+Y) say Y = 3 X = (4) The X+Y will be negative value and then Y^(X+Y) will not be an integer. so this can be false. Answer : 2 and 3. D is the answer.



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X and Y are integers, X is even and negative, Y is odd and positive. W
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22 Jun 2016, 05:11
The question says which of the following could be false
So, if X is 4 and Y is 3 then Statement 2 would be 3^1 which is 1/3 which isn't an integer.
Since the question specifies could be shouldn't the answer be D, since 2 could be false in certain cases and 3 is false.



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Re: X and Y are integers, X is even and negative, Y is odd and positive. W
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22 Jun 2016, 07:35
Divyadisha wrote: Bunuel wrote: X and Y are integers, X is even and negative, Y is odd and positive. Which of the following could be false?
1. (X + Y) is an odd number. 2. Y^(X + Y) is an integer. 3. X^Y is a positive number.
A. 2 only. B. 3 only. C. 1 and 3 only. D. 2 and 3 only. E. 1, 2 and 3. 1. (X + Y) is an odd number. even+odd= odd. True2. Y^(X + Y) is an integer. odd ^(even+odd)= odd ^odd= odd integer. True3. X^Y is a positive number.. ve even ^+ve odd= ve integer (odd power means the number will retain its sign). Not true.B is the answer for second case take x=4 and y=3.thats false. answer is D



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Re: X and Y are integers, X is even and negative, Y is odd and positive. W
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22 Jun 2016, 07:36
AvalonQQ wrote: The question says which of the following could be false
So, if X is 4 and Y is 3 then Statement 2 would be 3^1 which is 1/3 which isn't an integer.
Since the question specifies could be shouldn't the answer be D, since 2 could be false in certain cases and 3 is false. yes you are correct answer is D this is a COULD question not a MUST



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Re: X and Y are integers, X is even and negative, Y is odd and positive. W
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23 Jun 2016, 08:52
Bunuel wrote: X and Y are integers, X is even and negative, Y is odd and positive. Which of the following could be false?
1. (X + Y) is an odd number. 2. Y^(X + Y) is an integer. 3. X^Y is a positive number.
A. 2 only. B. 3 only. C. 1 and 3 only. D. 2 and 3 only. E. 1, 2 and 3. Inference X= Integer, EVEN, Negative Y= Integer, ODD, Positive Analyzing Statement 1 1. (X + Y) is an odd number. Let X = 2 Y = 5 then X + Y = 2 + 5 = 3 It will always be odd, 2. Y^(X + Y) is an integer. Let Y = 3 X= 2 than Y^(X + Y) = 3 ^ 1 = 1 If Y= 3 X = 4 Than Y^(X + Y) = 3 ^ (1) = 1 /3 there fore Could be False 3. X^Y is a positive number. Let X = 2 Y= 3 Since Y is Odd (X ) ^ Y will always be a Negative No There fore Could be False Answer 2 And 3 Correct me if am Wrong



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X and Y are integers, X is even and negative, Y is odd and positive. W
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20 Jul 2016, 14:03
Got tricked by the "could be" false. 1. Can't be False. For any pair of numbers that cointains 1 Even & 1 Odd we know that even + odd = always odd. So number 1 is out. 2. Can be False. Let's take for example X=2 & Y=5. 5^3 is an integer. But let's take X=10 & Y=3. 3^(7) = 1/3^7. Not an integer.3. Can be False. For example : X=2 & Y=3. That's a negative number Actually, any negative number in any odd power will be negative. So, only 2&3 COULD be False.
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Re: X and Y are integers, X is even and negative, Y is odd and positive. W
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20 Jul 2016, 21:55
Berlin77 wrote: Got tricked by the "could be" false.
1. Can't be False. For any pair of numbers that cointains 1 Even & 1 Odd we know that even + odd = always odd. So number 1 is out.
2.Can be False. Let's take for example X=2 & Y=5. 5^3 is an integer. But let's take X=10 & Y=3. 3^(7) = 1/3^7. Not an integer.
3. Can be False. For example : X=2 & Y=3. That's a negative number Actually, any negative number in any odd power will be negative.
So, only 2&3 COULD be False. "Could be false" is the negation of "must be true". Whatever is not "must be true", that is "could be false". 1 must be true since even + odd = always odd. Hence it is not "could be false". 2 is not "must be true". If X = 4 and Y = 3, 3^(4 + 3) = 1/3 (not an integer). Hence it is "could be false". 3 is not "must be true". If X = 4 and Y = 3, (4)^3 = 64 (not a positive integer). Hence it is "could be false".
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X and Y are integers, X is even and negative, Y is odd and positive. W
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21 Jul 2016, 09:22
Bunuel wrote: X and Y are integers, X is even and negative, Y is odd and positive. Which of the following could be false?
1. (X + Y) is an odd number. 2. Y^(X + Y) is an integer. 3. X^Y is a positive number.
A. 2 only. B. 3 only. C. 1 and 3 only. D. 2 and 3 only. E. 1, 2 and 3. 1. (X + Y) is an odd number  is always true odd (+) even is always odd !! 2. Y^(X + Y) is an integer.  3^(4+3)=3^1 is not an integer 3. X^Y is a positive number.  2^3=8 is not a positive number
therefore D



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Re: X and Y are integers, X is even and negative, Y is odd and positive. W
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17 Apr 2017, 04:02
Option DOdd: O, Even: E & Fraction: F. x = E & y = +O 1. (X + Y) is an odd number. : ( E + +O) = O or +O = O : True 2. Y^(X + Y) is an integer. : (+O)^(E + +O) = (+O)^(O or +O) = F or O 3. X^Y is a positive number. : (E)^(+O) = E
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Re: X and Y are integers, X is even and negative, Y is odd and positive. W
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22 Jul 2017, 12:11
1. (X + Y) is an odd number. Must be True 2. Y^(X + Y) is an integer. Could be False (IfX>Y in magnitude we get decimal say x=6,y=3, similarly if reversed i.e.Y>X say x=2,y=5 we get integer) 3. X^Y is a positive number. Must be False Given X and Y are integers, X is even and negative, Y is odd and positive. From this Option A seems correct which is an example of Could be rest should always be true or false.
Hence the question should be modified else it is misleading. Please advise.




Re: X and Y are integers, X is even and negative, Y is odd and positive. W
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