Compact fluorescent light (CFL) bulbs are growing in market share as a

Question

Compact fluorescent light (CFL) bulbs are growing in market share as a replacement for the standard incandescent light bulb. However, an even newer technology is emerging: the light-emitting diode (LED) bulb. Like CFL bulbs, LED bulbs are energy efficient, and they can last around fifty thousand hours, about five times as long as most CFL bulbs. Yet, a single LED bulb costs much more than five CFL bulbs.

The information in the passage above most supports which of the following conclusions?

The information in the passage above most supports which of the following conclusions?

A. LED bulbs are most likely to be used in locations where light bulbs would be difficult or costly to replace.

B. CFL bulbs will need to come down further in price in order to compete with LED bulbs.

C. LED bulbs are most likely to be used in locations where there is frequent accidental breakage of bulbs.

D. CFL bulb designs are likely to advance to the point where they can last as long as LED bulbs.

E. LED bulbs are likely to drop in price, to the point of being competitive with CFL bulbs.

ID: 500100
CR28001.02

GMATNinja · Accepted Answer

(E) could be true. In real life, (E) probably IS true. But our task isn't to determine what can or cannot be true -- take another look at the exact language of the question:
 
The passage tells us what LED light bulbs cost now but there's no information  in the passage  that could lead to the conclusion that the price of LED bulbs will drop in the future.

This means (E) cannot be the correct answer.

(A) tells us:
 
The author is using generic terminology when they say  light bulbs  in (A). They're using this generic terminology to emphasize that any light bulb (incandescent, CFL, or LED) could be used in these places.

The passage tells us that LED bulbs last around five times as long as a CFL bulb. So if someone wanted a light in a place where replacing the bulb was going to be difficult, dangerous, or costly, then using an LED bulb means they would have to replace the bulb far less frequently. The cost savings from not replacing the bulbs so frequently would balance out the LED bulb's greater cost.

The information in the passage  most supports  the conclusion given in (A), so (A) is the answer to this one.

I hope that helps!

shameekv1989 · Answer

Compact fluorescent light (CFL) bulbs are growing in market share as a replacement for the standard incandescent light bulb. However, an even newer technology is emerging: the light-emitting diode (LED) bulb. Like CFL bulbs, LED bulbs are energy efficient, and they can last around fifty thousand hours, about five times as long as most CFL bulbs. Yet, a single LED bulb costs much more than five CFL bulbs.

The information in the passage above most supports which of the following conclusions?

The information in the passage above most supports which of the following conclusions?

A) LED bulbs are most likely to be used in locations where light bulbs would be difficult or costly to replace.

B) CFL bulbs will need to come down further in price in order to compete with LED bulbs.

C) LED bulbs are most likely to be used in locations where there is frequent accidental breakage of bulbs.

D) CFL bulb designs are likely to advance to the point where they can last as long as LED bulbs.

E) LED bulbs are likely to drop in price, to the point of being competitive with CFL bulbs.

Let :-
LED's run for 500 hrs at a time before a need for replacement
CFL's run for 100 hrs before replacement

LED's cost 6$
CFL's cost 1$

For total 20000 hrs LED's cost 240$ and 40 replacements; CFL's cost 200$ and require 200 replacements

If a replacement cost is higher in a location then CFL's cost would overtake LED's cost since  CFL's would require many more replacements even though it is cost-efficient . 
 
 option A  relates to the above theory.

option B - CFL's are already cost-efficient to be competitive. 
option C - Accidental breakages would affect both LED's as well as CFL's equally
option D - Prediction can not be made for Must be true questions
option E - Predictions can not be made for Must be true questions

ArunSharma12 · Answer

CFL costs x then LED costs 5x
CFL lasts t hours then LED lasts 5t hours. 
Therefore in cost 5x we get 5 CFLs which last just as long as a single LED.
CFL already has the advantage in number of units in the same cost therefore LED needs to come down further in price to compete with CFLs

A) LED bulbs are most likely to be used in locations where light bulbs would be difficult or costly to replace.
 LED bulbs will be costlier in such places. Passage do not support this information

B) CFL bulbs will need to come down further in price in order to compete with LED bulbs.
 CFL bulbs already have advantage in number of units for the same price

C) LED bulbs are most likely to be used in locations where there is frequent accidental breakage of bulbs.
 This is opposite to what is supported by the passage

D) CFL bulb designs are likely to advance to the point where they can last as long as LED bulbs.
 This information is not supported by the passage, as passage does not indicate any advancements for CFL

E)  LED bulbs are likely to drop in price, to the point of being competitive with CFL bulbs.
 This is supported by the passage.

unraveled · Answer

Compact fluorescent light (CFL) bulbs are growing in market share as a replacement for the standard incandescent light bulb. However, an even newer technology is emerging: the light-emitting diode (LED) bulb. Like CFL bulbs, LED bulbs are energy efficient, and they can last around fifty thousand hours, about five times as long as most CFL bulbs. Yet, a single LED bulb costs much more than five CFL bulbs.
The information in the passage above most supports which of the following conclusions?

As per argument:
Premise: CFL market share increasing by replacing SIL. LED and CFL both are energy efficient. LED last 50,000 hrs which is 5X of CFL i.e. CFL lasts 10,000 hrs. 
Conclusion: Even if it is so, a single LED costs more than 5 CFLs.
One way to understand the argument is that using 'yet' author leaves us with a question mark and it does so, naturally. Why LED costs more? There must be something that caused such a situation. This might act as a clue for us also. Reason: That something is what must be true, supporting the conclusion.

A) LED bulbs are most  likely to be used  in locations where light bulbs would be difficult or costly to replace.

B) CFL bulbs  will need to come down  further in price in order to compete with LED bulbs.

C) LED bulbs are most  likely to be used  in locations where there is frequent accidental breakage of bulbs.

D) CFL bulb designs are  likely to advance  to the point where they can last as long as LED bulbs.

E) LED bulbs are  likely to drop  in price, to the point of being competitive with CFL bulbs.

B, D and E are straight out since all of them talk about future, whereas, we know that if something has to support a conclusion it must have to be true i.e. it must have happened in past. Please note the text in red which show that all of them are talking about which, at best, has no role to support - hypothetically or factually - the conclusion.

Left with A and C, C is opposite to what we are looking for. 
First of all, if something is being used frequently then directly or indirectly it is increasing the demand which eventually should lower the prices. If LEDs are being used frequently, thus more number of LEDs are being used so LED prices should lower which is not the case as per argument. And since we can't counter, rather should not counter the premise, this might not be true.  Additionally, frequency of accidental breakage is open-ended as we can consider any value as frequent.

Here itself, using POE, we can mark the answer as A even if we dodn't understand it.

But let's see what we have here. Since it is the first option we might be tempted to choose it even before eliminating all other choices. 
There are two things that should jump out to anyone - difficult and costly. If something is difficult to replace, it would cost more. For example - If an LED is used in mountainous terrain, it is very much likely to cost more for it needs more time and effort to reach those places, and it needs more resources than normal, costing more to replace.

Do note that the text in green. It shows that these things hae happened in the past and would most likely happen in future also.

Hope this is helpful...!!

Pooja1991 · Answer

Hi,

I am extremely confused between A and E. Why cant E be true? And especially usage of 'light bulbs' instead of CFL got me confused in option A. I though the author was being generic in terminology.

eshantrips · Answer

The easy way to look at the solution is by making a mental analysis:

1. Energy Efficiency: CFL = LED
2. Life: CFL < LED
3. Cost: CFL < LED

Now, we have to find which of the options can be the  conclusion of one or more of the above points/premises .

A) LED bulbs are most likely to be used in locations where light bulbs would be difficult or costly to replace.

This is interesting. This option brings in a fourth variable, i.e. Operation Cost. If the Operation Cost of the bulb is higher (in this case the cost of changing the bulb) then it will make sense to buy LED as the Overall cost of LED will be lower than CFL. --- Hence Correct

B) CFL bulbs will need to come down further in price in order to compete with LED bulbs.

This is a new premise and can not be linked to the above three premises

C) LED bulbs are most likely to be used in locations where there is frequent accidental breakage of bulbs.
 
 On the contrary, CFL should be used where accidental breakage of bulbs in frequent. As the breakage is frequent, the life of the product is irrelevant. In such a case the lower cost item should be the logical choice

D) CFL bulb designs are likely to advance to the point where they can last as long as LED bulbs.

Same as Option B. This is a new premise and can not be linked to the above three premises

E) LED bulbs are likely to drop in price, to the point of being competitive with CFL bulbs.

Again, same as Option B. This is a new premise and can not be linked to the above three premises

naveenban · Answer

A) LED bulbs are most likely to be used in locations where light bulbs would be difficult or costly to replace. -  Correct, As LED bulbs are expensive, they can be used only in such places that can match their high cost. 
B) CFL bulbs will need to come down further in price in order to compete with LED bulbs. -  Wrong. CFL bulbs are already cheaper than LED bulbs. 
C) LED bulbs are most likely to be used in locations where there is frequent accidental breakage of bulbs. -  Why would anyone buy 5 times more expensive bulbs when their is a frequent accidental breakage. 
D) CFL bulb designs are likely to advance to the point where they can last as long as LED bulbs. -  Out Of Scope 
E) LED bulbs are likely to drop in price, to the point of being competitive with CFL bulbs. -  Out Of Scope.

minirana · Answer

Thanks for your explanation.

But may i ask what is the conclusion of this CR question? i made an error in this because i couldnt understand the conclusion. I felt it was too absurb.
Is my approach to working out CR wrong?

yashikaaggarwal · Answer

The main highlight of the passage is why should one use LED over CFL if both of them are almost same. Except CFL is way cheaper. 
We have to state why should one continue using LED,
First statement testify same. LED should be used at the place where cost is not the factor. Only then one will be able to use LED over CFL. Otherwise CFL is way better than LED.

Posted from my mobile device

ShreyaKohli · Answer

Hi GMATNinja,

I am unable to understand this question.

Isn't this an inference type question? If yes, then how can answer choice A be the correct option? Answer choice A is bringing in information from outside which is not mentioned in the passage. For inference type of questions, we stick to the universe created by the argument.

In the answer choice A, the usage of these bulbs specific to location is mentioned which in my opinion is not mentioned in the argument and definitely cannot be inferred.

Or probably I am missing out some major point.

Please help!

Thanks,
Shreya

GMATNinja · Answer

The question asks which option is a  conclusion that is supported  by the information in the passage -- so that's what you're looking for in the correct answer choice.

Imagine that the conclusion of the passage is the information in (A): "LED bulbs are most likely to be used in locations where light bulbs would be difficult or costly to replace."

Would the information in the passage serve as  support  for this conclusion? Sure! We learned from the passage that LED's last much longer, and therefore don't need to be replaced as often. This would certainly support the idea that people will use LED's in hard-to-reach places.

Because the information in the passage provides support for (A), it is the correct answer.

It's best not to rely on overly-rigid rules about question "types" when attempting to answer a question. "Which of the following can be properly inferred?" is way different from "the information in the passage above most supports which of the following conclusions?"

Your best bet is to read the exact language of each question as it comes up, and then carefully answer that question.

I hope that helps!

aarkay87 · Answer

Hi  @GMATNinja

What is the right approach to solve the Conclusion type question? Like in other question types that you've answered , you start with sharing the right approach, for example:

Assumption Qs : "we want something that must be true for the argument to make sense"
 Boldface Qs : "When dealing with boldfaced questions, start by COMPLETELY IGNORING the boldface and finding the conclusion"

GMATNinja · Answer

In general, it's best to have a simple, flexible approach that will help you answer  any  CR question accurately. This is because while some questions fall neatly into "types," many other questions don't. So, you want to just take each question at face value instead of forcing it into a box that may or may not be a good fit. This overall approach is outlined in  this  article.

In regards to this particular question: we're asked to find a conclusion that is most supported by the information in the passage. Like with any CR question, you want to think about the structure of the argument. The only difference is that  we already know what role is played by the information in the passage  -- namely, the stuff in the passage MUST be support/evidence for one of the conclusions written in the answer choices.

With that in mind, take stock of the evidence presented in the passage:
  CFL's are replacing incandescent light bulbs 
 However, there's a new game in town: LED's 
 There is a similarity between LED's and CFL's: "they are energy efficient" 
 There is a reason why LED's are  better  than CFL's: "they can last around fifty thousand hours, about five times as long as most CFL bulbs." 
 There is a reason why LED's are  worse  than CFL's: "a single LED bulb costs much more than five CFL bulbs."

So, which answer choice is best supported by the evidence above? Let's look at (A) and (B):
 
This plays right into the evidence in the passage! The reason that LED's are  better  than CFL's is because they last much longer. So, you wouldn't have to replace LED's as frequently as you would have to replace CFL's. It follows that you'd want to use LED's in spots that are difficult/costly to reach, even if the LED's are more expensive.

(A) is looking good.

Hmm... this doesn't follow from the evidence presented. First, CFL's are  already  much cheaper than LED's, so it doesn't make sense to conclude that CFL's must become  even cheaper  in order to compete.

Furthermore, we don't know that CFL's are currently NOT competitive -- maybe a bunch of consumers prefer the cheaper option, even if LED's last much longer. So, we can't conclude that CFL's need to change in any way to be competitive.

Eliminate (B).

And, just like any other CR question, you should continue with POE to get to four wrong answers. The remaining answer -- (A), in this case -- is correct.

I hope that helps!

Sneha2021 · Answer

Hi Experts,
 VeritasKarishma   GMATNinja

A) LED bulbs are most likely to be used in locations where light bulbs would be difficult or costly to replace.
I agree that LED bulbs are likely to used in locations where other bulbs are costly to replace. But how can we derive the logic for "difficult to replace" 
Can we say for sure if something is "difficult to replace", it is definitely costly?
I think "difficult to replace" is define in terms of operations. How can we relate it with cost?
Please help to derive the logic behind the term.
Thanks!

KarishmaB · Answer

CFL & LED both are energy efficient.

CFL bulbs last 10k hours.
LED bulbs last 50k hours. So 1 LED = 5 CFLs

CFL bulbs cost say $2 per bulb.
LED bulbs cost more than $10 per bulb. Cost of 1 LED is more than 5 CFLs

So for the same usage duration, LED bulbs are more expensive than CFL bulbs. The problem with CFL will be that it will need to be changed 4 extra times. 
So what is supported?

A) LED bulbs are most likely to be used in locations where light bulbs would be difficult or costly to replace.

Correct. The only problem with CFLs is that they will require frequent replacing. So LEDs will be useful when replacing the bulbs is difficult such as put on a very high ceiling (difficult to reach) or in remote locations (expensive to go there and return) etc.

B) CFL bulbs will need to come down further in price in order to compete with LED bulbs.

CFL bulbs are already cheaper than LED bulbs.

C) LED bulbs are most likely to be used in locations where there is frequent accidental breakage of bulbs.

No. CFL bulbs are better there. LED bulbs are meant to run on and on.

D) CFL bulb designs are likely to advance to the point where they can last as long as LED bulbs.

We don't know whether they are likely to advance in such a way.

E) LED bulbs are likely to drop in price, to the point of being competitive with CFL bulbs.

Again, we don't know if they are likely to drop in price.

Answer (A)

GMATNinja · Answer

You're right that "difficult" does not  necessarily  mean "costly." Winning a gold medal at the olympics is difficult, for instance, but not necessarily  costly . However, we don't NEED to assume that difficult = costly for (A) to be the best answer.

Once we establish that "LED bulbs are likely to be used in locations where light bulbs are costly to replace," as you put it, (A) is already a pretty good candidate. But let's consider the word  "difficult"  separately.

Based on the passage, one advantage of LED bulbs is that they last five times longer than CFLs. So even though they are more than five times as expensive, they will need to be replaced less frequently. Therefore, if replacing light bulbs is  "difficult"  in certain locations, this could justify preferring LEDs to other types of bulbs. While this logic doesn't relate  directly  to the idea of cost, it is still  reasonable  -- presumably, people would prefer something easy over something difficult, so they could be willing to pay more for this advantage.

Your attention to the  exact words  of the passage is commendable, but be careful not to lose sight of the big picture while you're at it. For (A) to be correct, it just needs to provide reasons why people would prefer bulbs that need to be replaced less frequently (i.e. LEDs), even if they're pricier. Since it does just that, (A) is correct.

I hope that helps!

Namangupta1997 · Answer

Hi  AndrewN  
I narrowed down to A and C pretty easily. I was torn between whether "difficult and costly to replace" would be a more dominating factor to decide the use of LED over light bulbs or "frequent accidental breakage". I think since we are not given any info about about physical superiority of LEDs over light bulbs, there is a possibility that there is a frequent breakage of LEDs too at that place. This will lead to exorbitant costs instead.

In A, it would make more sense to install an LED where it is complicated make replacements as once an LED is installed, it would surely run for a decent amount of time.

Am I thinking on the right lines ?

AndrewN · Answer

Yes,  Namangupta1997 , you are thinking along the correct line of reasoning. I was not immediately taken with answer choice (A), but I did not see a solid reason to eliminate it. (C), however, goes against the narrative. Why would someone want to use expensive LED bulbs  in locations where there is frequent accidental breakage of bulbs ? It would probably make more sense to purchase the cheaper CFL bulbs and let them break with ready replacements in hand. Also, since these breakages are  accidental , we cannot say that perhaps someone would be more careful after installing LEDs. Answer choice (C) is simply not reasonably supported by the information in the passage. (We would have to bend over backwards in an effort to justify it.)

Meanwhile, answer choice (A), while not a definite outcome, makes sense from a financial and convenience perspective. To invoke an image,  difficult or costly to replace  can be thought of to mean that no one would want to be up on a ladder risking life and limb to replace a light bulb, so it might be better to pay more for a bulb upfront and not have to change it as frequently.

Well done on the question. Thank you for thinking to bring me into the dialogue.

- Andrew

findingmyself · Answer

GMATNinja

Why can't  B. CFL bulbs will need to come down further in price in order to compete with LED bulbs. be true? My logic is below:

LED: 50,000 hrs + 
 CFL: 10,000

Cost LED=100 
 Cost CFL=20

The above is FACTS given in the question

Now calculating cost efficiency(ROI): LED= 500(50000/100) 
 Now calculating cost efficiency(ROI)
: CFL= 10000/20=500

If Imagine CFL gets to a competitve pricing of Say 10 Rs 
 Then Cost efficiency is 10000/10=1000 
 Which means rather than having 1 LED light at 100 rs giving 50000 hours, we can have 10 LED bulbs at same cost giving 1,00,000/- hours. 
 This is exactly saying that if CFL prices need to come down further if they have to beat LED bulbs as per ROI

Where I am I going wrong?

Compact fluorescent light (CFL) bulbs are growing in market share as a

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GMAT Critical Reasoning (CR) Questions

Compact fluorescent light (CFL) bulbs are growing in market share as a

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