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Symb. DS

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Source: — Data Sufficiency |

by DeepakR » Wed May 13, 2009 1:15 am
The OA is A.

1. The operator can be either + or x regardless of that we can get that (5*6)*2=5*(6*2)

for *= + we get, (5+6)+2=5+(6+2) = 13
for *=x we get, (5x6)x2=30x2 =60= LHS and RHS = 5x(12)=60

Hence A is sufficient.

2. B can be either + or - for which we will have different results.

- Deepak
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Re: Symb. DS

by Vemuri » Wed May 13, 2009 1:39 am
Stmt1: From this statement, we know that * can either be + or X. Use these 2 functions in the equation provided in the question & will see that both the operations satisfy the equation. Hence sufficient.

Stmt2: From this statement, we know that * can either be + or -. Use these 2 functions in the equation provided in the question & will see that + satisfies the equation but - does not. Hence insufficient.

So, A is the answer
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Re: Symb. DS

by lunarpower » Wed May 13, 2009 3:27 am
sanjib wrote:The symbol *represent one of the four Arithmetic operation:+-x /
(5*6)*2=5*(6*2)?

Stm1. 5*6=6*5
Stm2. 2*0=2

The OA is A

But I think it is C


Source : Official Sample test 2[/u][/i]
no, it's (a).
with statement (1), you DON'T know the unique identity of the operation: it could be either "+" or "x".

HOWEVER, you're making a dreadful mistake:
ALWAYS MAKE SURE THAT YOU'RE ANSWERING THE ACTUAL QUESTION.

i know this sounds obvious, but let's have a 2nd look here:

the question is NOT: "what is the operation?"
the question IS: "is (5 * 6) * 2 = 5 * (6 * 2)?"
the answer to that question is YES for "+", and YES for "x". therefore, statement (1) gives you an unequivocal "YES" and is thus sufficient.

the fact that you don't know the exact nature of the operation is irrelevant.
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DS symbol

by sanjib » Wed May 13, 2009 6:19 am
Thank you all for the succint clarification after all ratified by BTG forum!!!!
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