Hi,
I thought this problem was a simple subsitution problem was I am unable to figure out how to solve for the correct answer
For all positive intergers, m, box around m = 3m when m is odd and box around m = m/2 when m is even. Which of the following is equivalent to box around 9 x box around 6?
When I reattempted the problem I set 9 = 3m which is 3 and 6 = 1/2M which is 12. then i multipled them together for 36. However, the correct answer is 27. What am i doing wrong?
Sorry I could not draw a box around the letter m or insert the pic into this window. If you need to see the problem, I attached it as a word doc. Thanks for your help.[/img]
Subsitution question?
This topic has expert replies
Hello,
For this problem you have to substitute whatever you value for M is into the equation 3M-odd or 1/2M-even
You was Given 9 as M and 6 as M
So you the formula tells you to substitute those values into the equation to get:
= [9]*3 times [6]*(1/2)
= 27 * 3
= 81
as you can see doing the same thing for [27] gives you 81 also.
For this problem you have to substitute whatever you value for M is into the equation 3M-odd or 1/2M-even
You was Given 9 as M and 6 as M
So you the formula tells you to substitute those values into the equation to get:
= [9]*3 times [6]*(1/2)
= 27 * 3
= 81
as you can see doing the same thing for [27] gives you 81 also.
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cneal4 wrote:Hello,
For this problem you have to substitute whatever you value for M is into the equation 3M-odd or 1/2M-even
You was Given 9 as M and 6 as M
So you the formula tells you to substitute those values into the equation to get:
= [9]*3 times [6]*(1/2)
= 27 * 3
Thanks for the feeback; however, the correct answer is per the GMAT is 27. I got the same answer as you but it is not correct. Could the test software be incorrect?
= 81
as you can see doing the same thing for [27] gives you 81 also.
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I found the correct way to solve this problem. Here is the link in case you want to know why the correct answer is 27
https://www.beatthegmat.com/please-expla ... 23590.html
https://www.beatthegmat.com/please-expla ... 23590.html
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hey anthony!
thanks for posting this question and the solution. unfortunately i still dont get it...... would you (or anyone else) try to explain to me why it is [27]?
i was absolutely certain that the answer should be 36 or [18] ...
thanks,
sven
thanks for posting this question and the solution. unfortunately i still dont get it...... would you (or anyone else) try to explain to me why it is [27]?
i was absolutely certain that the answer should be 36 or [18] ...
thanks,
sven
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- Junior | Next Rank: 30 Posts
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- Location: South NJ, right outside of Philly
- Thanked: 1 times
- GMAT Score:420
The correct answer is 27.
The question is asking which of the following is equivalent to (9) x (6)
When (m) is odd, we use the formula (m) = 3m. Therefore 9 is odd and we plug it into the formula. We now have (m) = 3*9 = 27 for the first part of the equation.
The second part of the equation states if we have an even number we use (m) = 1/2(m). We now have (6)*1/2 = 3 for the second part of the equation.
Now we put both numbers into the formula and solve: 27 * 3 = 81. Here is tricky part. 81 is an odd number and the question asks you which of the numbers below is equivalent to (9) x (6).
Since 81 is odd, we need to find what number works with the original formula, m = 3m. Now you need to plug and solve. (81) = 3m. This equals 27 and solves the problem.
It took me a while to figure this problem out too. I hope this explanation helps.
Anthony
The question is asking which of the following is equivalent to (9) x (6)
When (m) is odd, we use the formula (m) = 3m. Therefore 9 is odd and we plug it into the formula. We now have (m) = 3*9 = 27 for the first part of the equation.
The second part of the equation states if we have an even number we use (m) = 1/2(m). We now have (6)*1/2 = 3 for the second part of the equation.
Now we put both numbers into the formula and solve: 27 * 3 = 81. Here is tricky part. 81 is an odd number and the question asks you which of the numbers below is equivalent to (9) x (6).
Since 81 is odd, we need to find what number works with the original formula, m = 3m. Now you need to plug and solve. (81) = 3m. This equals 27 and solves the problem.
It took me a while to figure this problem out too. I hope this explanation helps.
Anthony