A critical Doubt

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A critical Doubt

by sivaelectric » Tue May 31, 2011 3:48 am
This is a very critical question which struck me today when I was solving one question. When we solve the question with the options provided should we get the same answer? Suppose if we are able to solve with both the options and get a different answer, can we still select D answer that both statement alone is sufficient. Please let me know.

Need expert advice on this please. :(
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by Frankenstein » Tue May 31, 2011 5:47 am
Hi,
I am not an expert. But, I take this opportunity as an attempt to resolve your issue. Probably, experts can confirm it later.
You can select D if you can solve with either statement alone irrespective of what you get the answer to be.

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by cans » Tue May 31, 2011 5:58 am
Yup you can select D
But in both cases there should be a unique answer
Say solving A) you get 5 and solving B) you get 10
Ans - D :)

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by SoCan » Tue May 31, 2011 6:01 am
According to MGMAT, the statements never contradict each other.

If you get different answers, then you've made a mistake. That doesn't mean the answer's not D - perhaps you just made a mistake in the calculation. But it also means you may have made an error in logic. If you get different answers, check your work. You don't necessarily need to recalculate everything, because the actual answer doesn't matter - just make sure can calculate the answer based on the information given.

I think I've noticed some of the questions posted on this board don't meet this standard, but MGMAT is pretty clear on this issue for the actual test.

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by SoCan » Tue May 31, 2011 6:08 am
I just noticed there's another thread on this page raising the same question. One of the experts confirmed what I wrote that the statements never contradict each other, but that some of the lower quality prep material or question on message boards aren't written well. He also wrote, "In general, if a prep company can't even get this simple aspect of DS structure right, I'd expect their materials would not be worth using."

https://www.beatthegmat.com/should-both- ... 51565.html

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by sivaelectric » Tue May 31, 2011 6:09 am
Guys answer this post. https://www.beatthegmat.com/percentages-t84054.html what would your answer be on that post. Please respond.
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by cans » Tue May 31, 2011 8:19 am
i read the percentages question. If that question appears in the exam, i am not going to calculate value of 'a' for each case.
from A it is obvious that I will get a single answer and from B also.
And thus will mark D.
If it's required that both the answers match, then the question should be of type problem solving because we are required to find the actual answer.
DS means just to find if data is sufficient to find unique answer.

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by sivaelectric » Tue May 31, 2011 8:59 am
Yeah cans, thats what I was saying and expert told me the answers should match. Thats the reason for this post. :)
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by SoCan » Tue May 31, 2011 9:03 am
cans wrote: DS means just to find if data is sufficient to find unique answer.
Yes, but it's useful to know that GMAT DS statements will not contradict each other, because it allows you to catch errors in your calculations that lead you to believe that a statement isn't sufficient when it actually is, or vice versa.

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by sivaelectric » Tue May 31, 2011 9:11 am
SoCan wrote:
cans wrote: DS means just to find if data is sufficient to find unique answer.
Yes, but it's useful to know that GMAT DS statements will not contradict each other, because it allows you to catch errors in your calculations that lead you to believe that a statement isn't sufficient when it actually is, or vice versa.
But I have question that contradicts and whats your opinion with this.
https://www.beatthegmat.com/percentages-t84054.html
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by SoCan » Tue May 31, 2011 9:49 am
sivaelectric wrote:
SoCan wrote:
cans wrote: DS means just to find if data is sufficient to find unique answer.
Yes, but it's useful to know that GMAT DS statements will not contradict each other, because it allows you to catch errors in your calculations that lead you to believe that a statement isn't sufficient when it actually is, or vice versa.
But I have question that contradicts and whats your opinion with this.
https://www.beatthegmat.com/percentages-t84054.html
It's not an official question, right?

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by Stuart@KaplanGMAT » Tue May 31, 2011 9:59 am
sivaelectric wrote:This is a very critical question which struck me today when I was solving one question. When we solve the question with the options provided should we get the same answer? Suppose if we are able to solve with both the options and get a different answer, can we still select D answer that both statement alone is sufficient. Please let me know.

Need expert advice on this please. :(
Hi,

if each statement seems sufficient but gives a different answer, there are two possibilities:

1) you have made a mistake (i.e. they're not both sufficient); and

2) it's not a proper GMAT question.

On the actual GMAT, the two statements will NEVER contradict one another. When (D) is the correct answer, the two choices will ALWAYS give the same answer to the question.

If you're working with official (or reputable) GMAT material, you'll never find a question on which the statements contradict. If you're working with random questions you found on the net, the statements do sometimes contradict - a sure sign to stop using those resources.

So, if you're working with a question you trust and get two different answers, that's an immediate sign that you've made a mistake and need to recheck your work.
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by sivaelectric » Tue May 31, 2011 6:35 pm
yes it is not an official question but they mentioned it clearly below the answer explanations that when you solve with both the options that
you dont have to get the same answer. you just need to find whether they are suitable for solving the question. It was also mentioned that it was a waste of time to solve for answers for DS on GMAT.
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by Stuart@KaplanGMAT » Tue May 31, 2011 7:58 pm
sivaelectric wrote:yes it is not an official question but they mentioned it clearly below the answer explanations that when you solve with both the options that
you dont have to get the same answer. you just need to find whether they are suitable for solving the question. It was also mentioned that it was a waste of time to solve for answers for DS on GMAT.
Just the fact that they make that statement is an indication of how poorly they understand the GMAT. What that really says is "STAY AWAY FROM OUR MATERIAL!!"
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by sivaelectric » Tue May 31, 2011 8:56 pm
But still they are one of the players in the field. Never mind. Will stop referring those material from now on. :) So Stuart, what you are saying is that both the answer should not contradict right. :)
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Chitra Sivasankar Arunagiri