When exercising the muscles in one’s back, it is important

Question

When exercising the muscles in one’s back, it is important, in order to maintain a healthy back, to exercise the muscles on opposite sides of the spine equally. After all, balanced muscle development is needed to maintain a healthy back, since the muscles on opposite sides of the spine must pull equally in opposing directions to keep the back in proper alignment and protect the spine.

Which one of the following is an assumption required by the argument?

Which one of the following is an assumption required by the argument?

(A) Muscles on opposite sides of the spine that are equally well developed will be enough to keep the back in proper alignment.

(B) Exercising the muscles on opposite sides of the spine unequally tends to lead to unbalanced muscle development.

(C) Provided that one exercises the muscles on opposite sides of the spine equally, one will have a generally healthy back.

(D) If the muscles on opposite sides of the spine are exercised unequally, one’s back will be irreparably damaged.

(E) One should exercise daily to ensure that the muscles on opposite sides of the spine keep the back in proper alignment.

Source: LSAT

GMATNinja · Accepted Answer

Thanks  Mahmud6  for the reply!

Let's look at the passage in terms of necessary and sufficient conditions. We are told that "balanced muscle development  is needed  to maintain a healthy back". Does that mean that balanced muscle development is SUFFICIENT to maintain a healthy back? Maybe not. Consider the following example:

A great GMAT score is needed to get accepted to LBS.

So if you get a great GMAT score, will you get accepted to LBS? Maybe, maybe not. Getting a great GMAT score is a NECESSARY condition, but it is not sufficient. You might need a great GMAT score, an outstanding essay, solid referrals, impressive work experience, etc. Similarly, having balanced muscle development is NECESSARY to maintaining a healthy back, but it might not be sufficient. You might need balanced muscle development, lots of flexibility, great posture, healthy vertebrae, etc.

Now take a look at choice (C):

Just because you exercise the muscles on opposite sides equally, does not necessarily mean you'll have balanced muscle development. And even if you have balanced muscle development, you might have an unhealthy back for other reasons.

The passage describes a NECESSARY condition, but choice (C) turns it into a (generally) SUFFICIENT condition. 100 people might have balanced muscle development, but half of them (or more) might have unhealthy backs for other reasons. This doesn't change the fact that having balanced muscle development is a NECESSARY condition. Thus, choice (C) is not a required assumption.

I hope that helps!

Squib17 · Answer

Premise: When exercising the muscles in one’s back, it is important, in order to maintain a healthy back, to exercise the muscles on opposite sides of the spine equally. 
Conclusion:  balanced muscle development is needed to maintain a healthy back  
Premise: since the muscles on opposite sides of the spine must pull equally in opposing directions to keep the back in proper alignment and protect the spine.

Which one of the following is an assumption required by the argument?

(A) Muscles on opposite sides of the spine that are equally well developed will be enough to keep the back in proper alignment.  I had marked this as the answer, but I guess I am wrong. Was confused between A and B]. in the premise it is mentioned we need a balanced muscle development, but option A uses the phrase " equally well developed" which I do not think is the same. 
If I try to negate it and say that it will not be enough to keep the back in proper alignement, it weakens the argument. Will be happy if someone can shed more light on my analysis.]

(B) Exercising the muscles on opposite sides of the spine unequally tends to lead to unbalanced muscle development.  If we negate this, we can easily say that this has to be the answer, because if exercising the muscles unequally does not tend to lead to unbalanced muscle development, then it would shatter the argument! Hence this has to be the answer. ]

(C) Provided that one exercises the muscles on opposite sides of the spine equally, one will have a generally healthy back. this is already mentioned, so this can't be an assumption! ]

(D) If the muscles on opposite sides of the spine are exercised unequally, one’s back will be irreparably damaged.  Out of Scope - No mention of irreparably damaged

(E) One should exercise daily to ensure that the muscles on opposite sides of the spine keep the back in proper alignment. Nothing is mentioned about daily exercise - out of scope. ]

So, looks like the answer should be B. But someone please highlight where is the mistake in my thought process in A.

Regards,
Squib

jinxd123 · Answer

When exercising the muscles in one’s back, it is important, in order to maintain a healthy back, to exercise the muscles on opposite sides of the spine equally. After all, balanced muscle development is needed to maintain a healthy back, since the muscles on opposite sides of the spine must pull equally in opposing directions to keep the back in proper alignment and protect the spine.

Which one of the following is an assumption required by the argument?

(A) Muscles on opposite sides of the spine that are equally well developed will be enough to keep the back in proper alignment.

(B) Exercising the muscles on opposite sides of the spine unequally tends to lead to unbalanced muscle development.

(C) Provided that one exercises the muscles on opposite sides of the spine equally, one will have a generally healthy back.

(D) If the muscles on opposite sides of the spine are exercised unequally, one’s back will be irreparably damaged.

(E) One should exercise daily to ensure that the muscles on opposite sides of the spine keep the back in proper alignment.

Using POE....

(A) Muscles on opposite sides of the spine that are equally well developed will be enough to keep the back in proper alignment.---Incorrect--- The passage does not state anything like this..(too extreme)

(B) Exercising the muscles on opposite sides of the spine unequally tends to lead to unbalanced muscle development.---Incorrect---Author does not talk about unbalanced muscle development, he rather talks about balanced muscle development..(out of scope)

(C) Provided that one exercises the muscles on opposite sides of the spine equally, one will have a generally healthy back.---Correct--If this is not true the argument falls apart.

(D) If the muscles on opposite sides of the spine are exercised unequally, one’s back will be irreparably damaged.---Incorrect---The passage does not state anything like this..(too extreme)

(E) One should exercise daily to ensure that the muscles on opposite sides of the spine keep the back in proper alignment.---Incorrect---The passage does not state anything like this..(generalization)

---

Thanks in advance for the Kudos I will recieve!!

KB04 · Answer

When exercising the muscles in one’s back, it is important, in order to maintain a healthy back, to exercise the muscles on opposite sides of the spine equally. After all, balanced muscle development is needed to maintain a healthy back, since the muscles on opposite sides of the spine must pull equally in opposing directions to keep the back in proper alignment and protect the spine.

Which one of the following is an assumption required by the argument?

(A) Muscles on opposite sides of the spine that are equally well developed will be enough to keep the back in proper alignment.

(B) Exercising the muscles on opposite sides of the spine unequally tends to lead to unbalanced muscle development.

(C) Provided that one exercises the muscles on opposite sides of the spine equally, one will have a generally healthy back.

(D) If the muscles on opposite sides of the spine are exercised unequally, one’s back will be irreparably damaged.

(E) One should exercise daily to ensure that the muscles on opposite sides of the spine keep the back in proper alignment.

Using POE....

(A) Muscles on opposite sides of the spine that are equally well developed will be enough to keep the back in proper alignment.---Incorrect--- The passage does not state anything like this..(too extreme)

(B) Exercising the muscles on opposite sides of the spine unequally tends to lead to unbalanced muscle development.---Incorrect---Author does not talk about unbalanced muscle development, he rather talks about balanced muscle development..(out of scope)

(C) Provided that one exercises the muscles on opposite sides of the spine equally, one will have a generally healthy back.---Correct--If this is not true the argument falls apart.

(D) If the muscles on opposite sides of the spine are exercised unequally, one’s back will be irreparably damaged.---Incorrect---The passage does not state anything like this..(too extreme)

(E) One should exercise daily to ensure that the muscles on opposite sides of the spine keep the back in proper alignment.---Incorrect---The passage does not state anything like this..(generalization)

---

Thanks in advance for the Kudos I will recieve!!

Mahmud6 · Answer

B. Exercising the muscles on opposite sides of the spine  un equally tends to lead to  un balanced muscle development.

Since we have two negative words we can paraphrase the sentence as below;
Exercising the muscles on opposite sides of the spine  equally  tends to lead to  balanced  muscle development.

So, by negating we get, 
Exercising the muscles on opposite sides of the spine  DOES NOT   equally  tends to lead to  balanced  muscle development.

This breaks down the conclusion, thereby, it is a correct assumption.

sunny91 · Answer

Hi Mahmud6,
Yes option B by negating, we can see the conclusion breaks. Can you kindly mention how C is incorrect. Even by negating C, the conclusion breaks.

Mahmud6 · Answer

Hi  sunny91 ,

Though I am still learning, I will try to present my reasoning.

The word 'generally' means 'in most cases' or 'usually'. So, to paraphrase the choice C, it stands-

'provided that one exercises the muscles on opposite sides of the spine equally, one will have a healthy back  in most cases '

So, by negating we get,

'provided that one exercises the muscles on opposite sides of the spine equally, one will  NOT  have a healthy back  in most cases  ---> which indicates that if one exercises the muscles on opposite sides of the spine equally,  in some cases one will have a healthy back.

I hope this doesn't break down the conclusion.

manishtank1988 · Answer

Good Afternoon Everyone 
Special thanks to  GMATNinja ,  KB04  and Hasan for their help and explanation. I only have 1 more question - 
How do we realize when to use necessary and sufficient point of reference and when to use simple negation. I hope my questions makes sense, because when seen as explained by GMATNINJA it makes sense but how to when to think on those lines, especially in exam when we all would only have few seconds?

So are there any markers we can look out for while reading CR for this kind of question?
Please explain.
Thanks

GMATNinja · Answer

I'm glad that you're enjoying our explanations,  manishtank1988 ! Sadly, there is no formula or algorithm for navigating these questions. As described in our  CR Guide for Beginners , you have to read carefully and think really hard about what's important in each unique passage.

When you see the words "is needed" in the phrase "balanced muscle development   is needed   to maintain a healthy back," you should be thinking, "okay, 'is needed'... this must be a  necessary  condition, not a sufficient one." There's no way around that part. If you are looking for cues/markers, trying too hard to group a passage with something you've seen in the past, and then trying to tackle it using an overly formulaic approach, you'll likely gloss over key details, fall for trap answers, and/or misinterpret something.

Sorry for the not-so-satisfying response, but I hope that helps a little bit!

aniket16c · Answer

Argument - Conclusion: To maintain a healthy back --> important to exercise X muscles equally 
By proper exercise --> muscles on the opposite side will be pulled equally in opposite direction --> balanced muscle development --> balanced development is required to maintain a healthy back.

(A) Muscles on opposite sides of the spine that are equally well developed will be enough to keep the back in proper alignment.
- The argument states that muscles are one of the most important (necessary) NOT the only parameter required (Sufficient). Hence this is an extreme option
- Wrong
 
(B) Exercising the muscles on opposite sides of the spine unequally tends to lead to unbalanced muscle development.
- To maintain a healthy back --> balanced development necessary. 
- Negate choice: Exercising X muscles does not tend to lead to unbalanced muscle development. Means even if same side muscles are exercised there wont be unbalanced development --> = there will be balanced development --> back will be maintained = contradicts the argument 
- Correct

(C) Provided that one exercises the muscles on opposite sides of the spine equally, one will have a generally healthy back.
- The argument is similar to the option A
- Provided that = Exercising the muscles on opposite sides is the only required parameter to maintain a healthy back. = Not necessary. May be the person has a dislocated back because of some congenital condition
- Wrong

(D) If the muscles on opposite sides of the spine are exercised unequally, one’s back will be irreparably damaged.
- The culprit is "irreparably damaged". The argument says that there wont be a balanced development --> spine cannot be maintained. But may be through some surgery we can align the back. So to say "irreparably" is incorrect.
- Wrong

(E) One should exercise daily to ensure that the muscles on opposite sides of the spine keep the back in proper alignment.
- This is an out of context argument.

Dear  daagh   nightblade354   GMATNinjaTwo  
If we modify the option D - If the muscles on opposite sides of the spine are exercised unequally, one’s back will be damaged
Can this be a better option than B as this option considers a direct effect on the final condition required to be attained than the effect proposed by option B?
Or will the two options be two close to arrive at a final answer?

auradediligodo · Answer

When exercising the muscles in one’s back, it is important, in order to maintain a healthy back, to exercise the muscles on opposite sides of the spine equally. After all, balanced muscle development is needed to maintain a healthy back, since the muscles on opposite sides of the spine must pull equally in opposing directions to keep the back in proper alignment and protect the spine.

Which one of the following is an assumption required by the argument?

Which one of the following is an assumption required by the argument?

Assumption question

Pre-thinking

Conclusion:  When exercising the muscles in one’s back, it is important, in order to maintain a healthy back, to exercise the muscles on opposite sides of the spine equally.

The argument gives us a reason according to which if we don't develop balanced muscles such muscles will unevenly pull in opposing directions and this action will damage our spine somehow.

Falsification scenario:   But what if people spine is not a perfect line and it might be a little oriented on the right or on the left? In such case the best thing should be to develop some muscles more on the left or on the right accordingly to the orientation of the spine

Assumption  : the spine is a straight line with the same amount of muscles n the right and on the left of it

POE:

(A) Muscles on opposite sides of the spine that are equally well developed   will be enough   to keep the back in proper alignment.
 The problem with this option is the highlighted portion since the passage states that a requirement for an healthy spine/back is that muscles are equally developed on both sides but there might as well be other requirements such as doing sports, having a correct position while sitting.....

(B)   Exercising the muscles on opposite sides of the spine unequally tends to lead to unbalanced muscle development.
 This option is very related to our pre-though assumption because it excludes the scenarios in which developing more muscles on one side than on the other side would be beneficial.

(C) Provided that one exercises the muscles on opposite sides of the spine equally, one will have a generally healthy back.
 Similar reasoning for choice A

(D) If the muscles on opposite sides of the spine are exercised unequally, one’s back will be irreparably damaged.
 Too extreme

(E) One should exercise daily to ensure that the muscles on opposite sides of the spine keep the back in proper alignment.
 out of scope

GMATNinja · Answer

Remember that we are looking for an assumption that is REQUIRED by the argument.

We don't necessarily NEED there to be damage for the argument to hold. All we need is UNBALANCED muscle development. So although (D) (both the original and your modified version) would help the argument, neither is a required assumption!

ashutosh_73 · Answer

Anything before FABS will be a conclusion 
FABS: For, After all, because, since

Conclusion:  While exercising, it is important, to maintain a healthy back, to exercise the muscles on opposite sides of the spine equally. 
 Intermediate conclusion:  balanced muscle development is needed to maintain a healthy back
 Premise:  the muscles on opposite sides of the spine must pull equally in opposing directions to keep the back in proper alignment and protect the spine.

Necessary assumption can be either between premise and int. conclusion OR Int. conclusion and Conclusion.

(A) Muscles on opposite sides of the spine that are equally well developed will be enough to keep the back in proper alignment.
 enough to keep? what if oxygen is also needed? Even then, conclusion holds true.    NOT THE NA

(B) Exercising the muscles on opposite sides of the spine unequally tends to lead to unbalanced muscle development.
 This bridges the gap between Int. conclusion and Conclusion.
balanced muscle development requires that one exercises the muscles on opposite sides of the spine equally

This choice is the contrapositive of the gap identified.

(C) Provided that one exercises the muscles on opposite sides of the spine equally, one will have a generally healthy back.
 ''Provided that'' is a necessary condition Marker. Argument doesn't assume that Only exercising muscles'' is a way to have healthy back. 
Maybe there are 50 MORE ways to have healthy ways, and conclusion still holds true.   NOT THE NA

(D) If the muscles on opposite sides of the spine are exercised unequally, one’s back will be irreparably damaged.
 Doesn't require the ''irreparable damage''.   NOT THE NA

(E) One should exercise daily to ensure that the muscles on opposite sides of the spine keep the back in proper alignment.
 Conclusion can be drawn properly even if ''one doesn't exercise DAILY''.   NOT THE NA

VerbalBot · Answer

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When exercising the muscles in one’s back, it is important

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When exercising the muscles in one’s back, it is important

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