For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when m is even. What is [9]*[6] equivalent to?
A. [81]
B. [54]
C. [37]
D. [27]
E. [18]
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For all positive integers m, [m]=3m when m is odd and
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rakeshd347
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GMATGuruNY
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Since @m=3m when m is odd, @9 = 3*9 = 27.For all positive integers m, @m=3m when m is odd and @m=(1/2)m when m is even. Which of the following is equivalent to @9 x @6?
A - @81
B - @59
C - @36
D - @27
E - @18
Since @m=(1/2)m when m is even, @6 = (1/2)6 = 3.
Thus, @9 * @6 = 27*3 = 81.
Notice the @ symbol in the answer choices.
The correct answer must be the EQUIVALENT of 81.
Answer choice D: @27
Since @m=3m when m is odd, @27 = 3*27 = 81.
The correct answer is D.
Answer choice A is A TRAP.
Always beware of an answer choice that seems TOO EASY or TOO OBVIOUS.
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vinay1983
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How is the answer 27?Please explainGMATGuruNY wrote:Since @m=3m when m is odd, @9 = 3*9 = 27.For all positive integers m, @m=3m when m is odd and @m=(1/2)m when m is even. Which of the following is equivalent to @9 x @6?
A - @81
B - @59
C - @36
D - @27
E - @18
Since @m=(1/2)m when m is even, @6 = (1/2)6 = 3.
Thus, @9 * @6 = 27*3 = 81.
Notice the @ symbol in the answer choices.
The correct answer must be the EQUIVALENT of 81.
Answer choice D: @27
Since @m=3m when m is odd, @27 = 3*27 = 81.
The correct answer is D.
Answer choice A is A TRAP.
Always beware of an answer choice that seems TOO EASY or TOO OBVIOUS.
You can, for example never foretell what any one man will do, but you can say with precision what an average number will be up to!
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theCodeToGMAT
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[m] = 3m ODD
[m] = m/2 EVEN
[9] * [6]
= 27 * 3
= 81
= [27]
Answer [spoiler]{D}[/spoiler]
[m] = m/2 EVEN
[9] * [6]
= 27 * 3
= 81
= [27]
Answer [spoiler]{D}[/spoiler]
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Jeff@TargetTestPrep
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We are given that [m] = 3m when m is odd, and [m] = (1/2)*m when m is even, and we must determine the value of [9]*[6].rakeshd347 wrote:For all positive integers m, [m]=3m when m is odd and [m]=(1/2)*m when m is even. What is [9]*[6] equivalent to?
A. [81]
B. [54]
C. [37]
D. [27]
E. [18]
Since 9 is odd, [9] = 3 x 9 = 27.
Since 6 is even, [6] = (1/2) x 6 = 3.
Thus, [9]*[6] = 27 x 3 = 81.
Now we must determine which "bracketed" answer choice is equal to 81.
Since 27 is odd, we see that [27] = 27 x 3 = 81.
Answer: D
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Brent@GMATPrepNow
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9 is odd, so [9] = (3)(9) = 27[m] = 3m for all odd m; [m] = (1/2)(m) for all even m. solve [9] X [6]?
A. [81]
B. [54]
C. [37]
D. [27]
E. [18]
6 is even, so [6] = 6/2 = 3
So, [9] x [6] = 27 x 3 = 81
BEFORE you select A, notice that 81 has brackets around it.
Since 81 is odd, [81] = (3)(81) = 243
So, answer choice A is NOT correct.
So, which of the 5 answer choices equals 81?
Since 27 is odd, [27] = (3)(27) = 81
So, the correct answer is D
Cheers,
Brent
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Brent@GMATPrepNow
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Brent@GMATPrepNow wrote:9 is odd, so [9] = (3)(9) = 27[m] = 3m for all odd m; [m] = (1/2)(m) for all even m. solve [9] X [6]?
A. [81]
B. [54]
C. [37]
D. [27]
E. [18]
6 is even, so [6] = 6/2 = 3
So, [9] x [6] = 27 x 3 = 81
BEFORE you select A, notice that 81 has brackets around it.
Since 81 is odd, [81] = (3)(81) = 243
So, answer choice A is NOT correct.
So, which of the 5 answer choices equals 81?
Since 27 is odd, [27] = (3)(27) = 81
So, the correct answer is D
Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
