Whats the QA..japan1453 wrote:Could you explain this. Thanks
D
I am getting D
Operatinons +,-,x
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malhotneha
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I am getting D
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gaggleofgirls
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Think first about the different operands...
+ and * are commutative, meaning a+b = b+a and a*b = b*a
- is not, meaning a-b not = b-a
1) k @ 1 is not equal to 1 @ k for all numbers means that @ cannot be + or *, so it must be -. At this point, the equation is irrelevant, you have the information you need to solve it, so you know 1 is sufficient.
2) @ represents subtraction is the same as 1), so 2 is sufficient.
Answer = D.
-Carrie
+ and * are commutative, meaning a+b = b+a and a*b = b*a
- is not, meaning a-b not = b-a
1) k @ 1 is not equal to 1 @ k for all numbers means that @ cannot be + or *, so it must be -. At this point, the equation is irrelevant, you have the information you need to solve it, so you know 1 is sufficient.
2) @ represents subtraction is the same as 1), so 2 is sufficient.
Answer = D.
-Carrie
Choice 1 states that K.1 is not equal to 1.K for SOME numbers of K.
Considering . to be -ve, you have two cases
Case 1: What if K is -ve (example - 2)?
K-1 => -2-1 =>-3
1-K => 1- -2 =>3
-3 not equals 3
Case 2: What if K is +ve(example 2)?
K-1 => 2-1 =>1
1-K => 1- 2 =>-1
-1 not equals 1
In both the cases, it doesn't comply. So I am not sure if case 1 would be sufficient to answer the question.
IMO B
Considering . to be -ve, you have two cases
Case 1: What if K is -ve (example - 2)?
K-1 => -2-1 =>-3
1-K => 1- -2 =>3
-3 not equals 3
Case 2: What if K is +ve(example 2)?
K-1 => 2-1 =>1
1-K => 1- 2 =>-1
-1 not equals 1
In both the cases, it doesn't comply. So I am not sure if case 1 would be sufficient to answer the question.
IMO B
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sanju09
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IMO DGID09 wrote:Choice 1 states that K.1 is not equal to 1.K for SOME numbers of K.
Considering . to be -ve, you have two cases
Case 1: What if K is -ve (example - 2)?
K-1 => -2-1 =>-3
1-K => 1- -2 =>3
-3 not equals 3
Case 2: What if K is +ve(example 2)?
K-1 => 2-1 =>1
1-K => 1- 2 =>-1
-1 not equals 1
In both the cases, it doesn't comply. So I am not sure if case 1 would be sufficient to answer the question.
IMO B
If k # 1 is not equal to 1 # k for some values of k, then # definitely cannot be a sign of addition or multilication. This makes us believe that # represents the sign of subtraction, proving the statement 1 sufficient to answer it. D is the correct answer.
The mind is everything. What you think you become. -Lord Buddha
Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
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Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001
www.manyagroup.com
