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# The operation* represents either addition, subtraction, or

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Updated on: 03 Jul 2013, 08:49
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45% (medium)

Question Stats:

54% (00:56) correct 46% (00:48) wrong based on 636 sessions

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The operation* represents either addition, subtraction, or multiplication of integers, what is the value of 1*0?

(1) 0*2=2
(2) 2*0=2

Originally posted by vaivish1723 on 23 Jan 2010, 00:25.
Last edited by Bunuel on 03 Jul 2013, 08:49, edited 1 time in total.
Edited the question and the OA.
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23 Jan 2010, 01:35
1
6
vaivish1723 wrote:
9
The operation* represents either addition, subtraction, or multiplication of integers,
what is the value of 1*0?
(1) 0*2=2
(2) 2*0=2

OA is

Why cant the OA is D because using statement II we get the same answer and we can use that to solve 1*0.

(1) 0*2=2 --> operation * represents addition --> 1*0=1+0=1. Sufficient.

(2) 2*0=2 --> operation * represents either addition or subtraction --> 1*0=1+0=1 and 1*0=1-0=1, the same answer. Sufficient.

OA must be wrong.
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10 Dec 2011, 17:48
1
The operation* represents either addition, subtraction, or multiplication of integers, what is the value of 1*0?

(1) 0*2=2
(2) 2*0=2
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10 Dec 2011, 18:35
ashiima wrote:
The operation* represents either addition, subtraction, or multiplication of integers, what is the value of 1*0?
(1) 0*2=2
(2) 2*0=2

We know that * is a plus sign, a minus sign, or a multiplication sign. If Statement 1 is true, the '*' symbol must be a plus sign, since the equation in Statement 1 won't be true if '*' is subtraction or multiplication. Since * represents addition, 1*0 = 1+0 = 1, and Statement 1 is sufficient.

For Statement 2, we know 2*0 = 2. This would be true if * is either addition or subtraction; * cannot be multiplication. So we know that 1*0 is either equal to 1+0 = 1, or is equal to 1-0 = 1. Either way its value is 1, so Statement 2 is also sufficient.

The answer is D (the OA given above is not right).
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12 Dec 2011, 13:40
Agree D. I think the source picked A because you are unsure of the sign in statment 2 however this does not affect the outcome of 1*0
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03 Jul 2013, 08:47
Bunuel wrote:
vaivish1723 wrote:
9
The operation* represents either addition, subtraction, or multiplication of integers,
what is the value of 1*0?
(1) 0*2=2
(2) 2*0=2

OA is

Why cant the OA is D because using statement II we get the same answer and we can use that to solve 1*0.

(1) 0*2=2 --> operation * represents addition --> 1*0=1+0=1. Sufficient.

(2) 2*0=2 --> operation * represents either addition or subtraction --> 1*0=1+0=1 and 1*0=1-0=1, the same answer. Sufficient.

OA must be wrong.

Hi Bunuel,

Operation from statement 1: You assumed 0*2 is an "addition" operation i.e. a*b = a +b. But couldn't it be assumed that a*b could also be = b-a (subtraction) ?. And hence 0*2 = 2-0 = 2. Isn't this statement insufficient because of 2 scenarios?

Where as in statement 2: 2*0 could be 2-0 = 2 or 2+0= 2. In either case, this statement alone is sufficient. Hence answer is B.

Am I missing something ?

Best
Rohan
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03 Jul 2013, 09:06
RohanKhera wrote:
Bunuel wrote:
vaivish1723 wrote:
9
The operation* represents either addition, subtraction, or multiplication of integers,
what is the value of 1*0?
(1) 0*2=2
(2) 2*0=2

OA is

Why cant the OA is D because using statement II we get the same answer and we can use that to solve 1*0.

(1) 0*2=2 --> operation * represents addition --> 1*0=1+0=1. Sufficient.

(2) 2*0=2 --> operation * represents either addition or subtraction --> 1*0=1+0=1 and 1*0=1-0=1, the same answer. Sufficient.

OA must be wrong.

Hi Bunuel,

Operation from statement 1: You assumed 0*2 is an "addition" operation i.e. a*b = a +b. But couldn't it be assumed that a*b could also be = b-a (subtraction) ?. And hence 0*2 = 2-0 = 2. Isn't this statement insufficient because of 2 scenarios?

Where as in statement 2: 2*0 could be 2-0 = 2 or 2+0= 2. In either case, this statement alone is sufficient. Hence answer is B.

Am I missing something ?

Best
Rohan

In (1) the operation cannot be subtraction, since $$0-2=-2$$ and not 2, as stated. But even if you were right, so suppose the operation can be addition or subtraction (as in the second statement), still (1) would be sufficient because we need to find the value of 1*0 which is the same for either of these two operations (+ or -).

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Hope it helps.
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03 Jul 2013, 09:39
Bunuel, Thanks for you reply. However by subtraction, I meant 2-0=2 not 0-2=-2. i.e. the operation 0*2 can be construed as addition (like you said) i.e. 2+0=2 or subtraction i.e 2-0=0. Please note that for subtraction, I am considering the case: a*b=b-a (which is 2-0 = 2) and not a-b (which is 0-2=-2) . hope my query is clear to you ?
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03 Jul 2013, 10:13
RohanKhera wrote:
Bunuel, Thanks for you reply. However by subtraction, I meant 2-0=2 not 0-2=-2. i.e. the operation 0*2 can be construed as addition (like you said) i.e. 2+0=2 or subtraction i.e 2-0=0. Please note that for subtraction, I am considering the case: a*b=b-a (which is 2-0 = 2) and not a-b (which is 0-2=-2) . hope my query is clear to you ?

Notice that the first statement is 0*2 not 2*0.
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18 Oct 2014, 12:40
D.

From 1, * cannot be multiplication and subtraction. so 1+0 = 1
From 2, * can be addition or subtraction, but 1-0 = 1 or 1+0 = 1

Thus both statement sufficient. Please check what question is asking this is good trap that test makers exploit.

vaivish1723 wrote:
The operation* represents either addition, subtraction, or multiplication of integers, what is the value of 1*0?

(1) 0*2=2
(2) 2*0=2

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01 Oct 2016, 21:46
Even if in the second statement the operator can be both + and -
the question stem will will have same value with both the operators. hence Both are correct
IMO D
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23 Apr 2019, 22:43
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