One of Two Arithmetic Operations

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One of Two Arithmetic Operations

by skalevar » Sat Oct 16, 2010 4:21 pm
If # denotes one of two arithmetic operations, addition or multiplicatio, and if k is an integer, what is the value of 3 # k?

1) 2 # k =3
2) 1 # 0 = k

OA is A.

I answered E.

Please explain your reasoning.

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by ksundar » Sat Oct 16, 2010 4:47 pm
With the stem, we know k is an integer.
From statement 1, 2#k=3 we can deduce that # is addition and k can take the value of 1 only.
From the second statement, we cannot say what the sign is or what the value of k can be. Not Sufficient.

So the answer is A.

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by ezhilkumarank » Sat Oct 16, 2010 5:00 pm
skalevar wrote:If # denotes one of two arithmetic operations, addition or multiplicatio, and if k is an integer, what is the value of 3 # k?

1) 2 # k =3
2) 1 # 0 = k

OA is A.

I answered E.

Please explain your reasoning.
The option in the DS question is sufficient only if it yields a single value for the unknown.

With Statement one: K could have only one value to satisfy the given equation. That is k could be only 1 and the operation could be only addition with the given constraints in the question.

With Statement two: K could be either 1 with # being addition or 0 when # is multiplication. Hence the original question 3#k could have two values. Hence this statement is not sufficient.
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by this_time_i_will » Sun Oct 17, 2010 12:59 am
skalevar wrote:If # denotes one of two arithmetic operations, addition or multiplicatio, and if k is an integer, what is the value of 3 # k?

1) 2 # k =3
2) 1 # 0 = k

OA is A.

I answered E.

Please explain your reasoning.
I think you forgot to consider that K is an integer and hence, for stmt. I: k can not be 3/2.