For every positive integer m, m = 3m , when m is odd and m= m/2, when m is even. What is the value of 9*6?
A.) 81
B.) 54
C.) 36
D.) 27
E.) 18
OA: C
Can someone clarify why A is wrong?
NOTE: There was a symbol around m in the Prep s/w. Since i couldnt post the symbol, have modified it to italics.
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For all positive integers m,[m] = 3m when m is odd and [m] = m/2 when m is even. Which of the following is equivalent to [9]*[6]?sathishkumarjva9888 wrote:For every positive integer m, m = 3m , when m is odd and m= m/2, when m is even. What is the value of 9*6?
A.) 81
B.) 54
C.) 36
D.) 27
E.) 18
OA: C
Can someone clarify why A is wrong?
NOTE: There was a symbol around m in the Prep s/w. Since i couldnt post the symbol, have modified it to italics.
Now [m] = 3m if m is odd, and [m] is m/2 if m is even.
[9] = 3 * 9 = 27
[6] = 6/2 = 3
So [9] * [6] = 27 * 3 = 81 = 3 * 27 = [27]
The correct answer is D.
Note that in the original question, the answer choices are also in squares, which means 81 = 3 * 27 = [27], according to the given symbols. So, you solved it right, but in the end you got trapped in choosing the correct answer. I hope you get my point.
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Thanks anurag.
But i still do not understand why should we again split 81 as 3*27.
Is it because the question was to find the equivalent of [9]*[6] and not the value of [9]*[6]??
I would like to know how to tackle these kind of traps. The question seemed really easy but never gave a thought that i should split up 81 again.
But i still do not understand why should we again split 81 as 3*27.
Is it because the question was to find the equivalent of [9]*[6] and not the value of [9]*[6]??
I would like to know how to tackle these kind of traps. The question seemed really easy but never gave a thought that i should split up 81 again.
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It is just because the answer choices are not given without square symbol, and in the question itself it is clearly mentioned that for an odd integer m, [m] = 3msathishkumarjva9888 wrote:Thanks anurag.
But i still do not understand why should we again split 81 as 3*27.
Is it because the question was to find the equivalent of [9]*[6] and not the value of [9]*[6]??
I would like to know how to tackle these kind of traps. The question seemed really easy but never gave a thought that i should split up 81 again.
So, [27] = 3 * 27 = 81
Now if you look at the answer choices it is not simply 81, it is within a square, which means if you choose [81] as the correct answer then [81] = 3 * 81, which is not the case.
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Thanks for pointing that Anurag. ![Smile :)](./images/smilies/smile.png)
So, i should see [9]*[6] = 81 as [27] and not as plain 81. I presume the word "equivalent" in the question stem is the key for me to look at each answer choice with [].
Correct me if i am wrong.
![Smile :)](./images/smilies/smile.png)
So, i should see [9]*[6] = 81 as [27] and not as plain 81. I presume the word "equivalent" in the question stem is the key for me to look at each answer choice with [].
Correct me if i am wrong.
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Yes, that's right.sathishkumarjva9888 wrote:Thanks for pointing that Anurag.
So, i should see [9]*[6] = 81 as [27] and not as plain 81. I presume the word "equivalent" in the question stem is the key for me to look at each answer choice with [].
Correct me if i am wrong.
[9] * [6] = 81 = [27]
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