The rise in free, do-it-yourself instructions on the Internet for home

Hello Supriya,

The rise in free, do-it-yourself instructions on the Internet for home repairs has led to a decrease in revenue for home service technicians and an increase in the number of injuries caused by people who have attempted home repairs themselves. Unfortunately, not all of the do-it-yourself instructions on the Internet are written as well as they should be.

What the passage tells us is that there is a reduction in the revenue for home service technicians and an increase in the number of injuries caused by the people who have attempted home repairs themselves. The passage further mentions that this is because do-it yourself(diy) instructions are not as good as they should be. Our aim is to find which of the stated options could be inferred from the passage.

Now, let us analyze statements b and c.

b) Most people who are injured while attempting home repairs have done so while following instructions found in free do-it-yourself instructions on the Internet.

The passage does mention that the do-it-yourself instructions are not up to mark. However, nowhere does the passage suggest that the instructions are wrongfully written or have some flaws which led to the increase in accidents. We cannot even be sure of whether those who met with accidents followed the instructions states in the diy manuals religiously. They could have committed some mistakes which might have led to accidents. Since, we cannot be completely sure of whether option b is true or not, based on the information in the passage, this statement in clearly not the one we are looking for.

Now, let us analyze option c.

c) The overall sale of online do-it-yourself home repair instructions by home service technicians has not been equal to the loss of revenue the technicians have incurred due to free offerings of this sort of material.

We already know that the free sale of online diy home repair instructions has caused a decrease in revenue for home service technicians. Statement c tells us that home technicians also sell the diy home repair instructions online. However, even though they might sell these instructions online, the revenue generated by this sale would not be equal to the decrease in revenue due to free offerings. If these values were equal, then they would not have incurred any decrease in net revenue at all. They would have either faced a no profit-no loss situation or a profitable earnings as their loss in revenue earned by home repair would have been negated by profit generated by online sale of diy instruction manuals. However, the passage mentions that there is a reduction in revenue for home technicians and hence, this statement can be inferred.

Hope this helps! Let me know if you need any further clarification.

Dear Sid,
I'm happy to respond to you.

Here's the argument again.
The rise in free, do-it-yourself instructions on the Internet for home repairs has led to a decrease in revenue for home service technicians and an increase in the number of injuries caused by people who have attempted home repairs themselves. Unfortunately, not all of the do-it-yourself instructions on the Internet are written as well as they should be.

Which of the following can be inferred from the argument above?
First of all, here's a blog about inference on the GMAT CR:
https://magoosh.com/gmat/2013/gmat-criti ... inference/
Here's a related blog on inference on the GMAT RC:
https://magoosh.com/gmat/2012/inference- ... rehension/

(C) The overall sale of online do-it-yourself home repair instructions by home service technicians has not been equal to the loss of revenue the technicians have incurred due to free offerings of this sort of material.
Have "home service technicians" offered sales of "online do-it-yourself home repair instructions"? We have no direct evidence. It's plausible that at least a few technicians did this somewhere ---- we have no guarantee that it is widespread in any way. This very carefully about what choice (C) says. Let
X = dollar value of gain in the sales of online do-it-yourself home repair instructions
Y = dollar value of the lose in revenue from the decline in home service calls
All choice (C) is saying is: X < Y. That's all it's saying. Even if no "home service technicians" anywhere offered anything online, then X = 0, but the inequality proposed by (C) is still true. Because the "home service technicians" have experience a "a decrease in revenue", we absolutely know that any gains they had were overshadowed by their losses. That's what makes this a very solid inference.

(E) As more free do-it-yourself instructions for home repairs are made available on the Internet, home service technicians will suffer more losses in revenue.
Hmmm. This could be true. Maybe, online instructions will increase and fewer people will contact home service technicians. Maybe. BUT, maybe it's true that the market has already stabilized. Maybe all the people who are inclined to be do-in-yourself-ers have already stopped using home service technicians, and maybe the people who are still paying the home service technicians for repairs are those people who have no intention whatsoever of ever doing any repair themselves. Therefore, we cannot necessarily infer (E).
As a general rule, just because a market has been moving in a certain direction for some period of time is most certainly no guaranteed that this direction will continue unabated into the future. Even a casual study of the stock market will reveal this abundantly. Markets start, stop, and reverse on a dime, without any prior warning. Any inference that posits an unlimited continuation of any market condition is on very shaky ground.

All this is why (C) is a much better answer than (E). Does all this make sense?
Mike
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Free DIY instructions for home repairs have increased.
This has led to decrease in revenue for home service techs. (their services and/or products are used less)
People attempting home repairs are causing more injuries. (to themselves or their family members, we don't know)
Not all DIY instructions are written well (free or paid, not known)

We are looking for inference:

(A) The number of people who are not home repair technicians and who have been injured while attempting home repairs has increased.

We know that people doing home repairs themselves are causing more injuries - to whom we don't know. Hence we don't know whether they themselves are being injured. So we don't know if this number has increased.

(B) Most people who are injured while attempting home repairs have done so while following instructions found in free do-it-yourself instructions on the Internet.

Again, who is getting injured we don't know and what instructions they were following, we don't know.

(C) The overall sale of online do-it-yourself home repair instructions by home service technicians has not been equal to the loss of revenue the technicians have incurred due to free offerings of this sort of material.

We know that revenue of home service technicians has gone down due to free DIY instructions. So whatever gain they might have had is not equal to the loss they suffered due to free offerings. They are seeing an overall loss. No effort of theirs is making up for the loss since they are seeing reduced effort. This option tells us that A (sale of DIY by them) is not making up the loss. This must be true.

(D) Most free do-it-yourself home repair instructions found on the Internet do not provide enough clear information regarding safety precautions.

We know that all DIY instructions are not good enough. Some might be good, some may not be good. Which ones - free or paid - are not good, we don't know.

(E) As more free do-it-yourself instructions for home repairs are made available on the Internet, home service technicians will suffer more losses in revenue.
We can infer nothing about what will happen in the future.

Answer (C)
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hi,

here the correct option C :The overall sale of online do-it-yourself home repair instructions by home service technicians has not been equal to the loss of revenue the technicians have incurred due to free offerings of this sort of material.

it assumes home technician is the same group which is making this free site of DO IT YOURSELF.
but there is no where in the argument given regarding this.
please suggest such assumptions aree correct?

regards

A cannot be inferred because the author talks only about injuries caused and not to whom exactly it is caused and also number of injuries doesn't exactly equate to the number of people getting injured.

B cannot be inferred because the author only says that there is only an increase in the injuries because internet instructions are followed but that doesn't mean that most of the injuries are caused while following the internet instructions

C can be inferred because the author says there is a decrease in the revenue of the home service technicians and so any income they could have gained due to sale of the online material is less than the revenue they lost due to the free online material

D cannot be inferred because the author doesn't talk about safety precautions at all, only that the instructions are not well written

E cannot be inferred because the author doesn't indicate anything about the future of the home service technicians.
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The question does not mention that the the home service technicians made online instructions. In addition, it says the online instructions are free. How could the technicians gain any cents of revenue from "selling them"?. C is not correct and this is not a good GMAT question.

Hi,

We have to either assume that online instructions were sold by the home service technicians or they were not when nothing is mentioned about that. In the former case the inference follows because the revenue of the home service technicians decreased. In the latter case we have to take the sale as zero because that is what finally it boils down to. Thus the inference still follows. But the wording of choice C suggests the first assumption.

Not all online instructions are free. The author only talks about the rise of free online instructions. So online instructions were also sold.
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This is an inference question therefore you read for the facts of the passage and then look for things that are not necessarily true to eliminate answers.

well, the only problem with option "c" is that no where it is written that home technicians also sell services online. Well, option "e" might get a fair chance to win as it show a cause effect relation and if we take all information in premise true then as thumb rule [ of GMAT makers] all effect will have only mentioned cause and will always apply.

Hi Mike

Thanks for the explanation given.
Can you throw some light on why B is incorrect , it seemed to me the best choice initially.

Dear akhil911,
I'm happy to help.

Here's the argument again, with choice (B).

The rise in free, do-it-yourself instructions on the Internet for home repairs has led to a decrease in revenue for home service technicians and an increase in the number of injuries caused by people who have attempted home repairs themselves. Unfortunately, not all of the do-it-yourself instructions on the Internet are written as well as they should be.

Which of the following can be inferred from the argument above?

(B) Most people who are injured while attempting home repairs have done so while following instructions found in free do-it-yourself instructions on the Internet.

Remember, in order for something be to be "inferred" on the GMAT CR or RC, it must be absolutely indisputable, guaranteed by God, true and justifiable beyond any shadow of a doubt. On inference questions, beware of being drawn into assumptions or loose suggestions. See these two posts:
https://magoosh.com/gmat/2013/gmat-criti ... inference/
https://magoosh.com/gmat/2012/inference- ... rehension/

The argument say that people are trying repairs more on their own and are getting hurt. OK, stop here. Why are they getting hurt? Maybe they are too cheap to pay for the repairman but are mechanically incompetent. Maybe they are following books that are not very clear. Maybe the are relying on manuals that come with products, that contain insufficient information to do sophisticated repairs. Maybe they don't know the proper precautions for their tools. Maybe the poorly made tools malfunctioned. etc. etc. etc. We can imagine many many reasons.

Then, the argument follows that fact with the statement: repair instructions on the Internet are bad. This juxtaposition elicits the assumption that the folks who were hurt doing repairs were injured precisely because they were following faulty Internet instructions. That's the assumption the text encourages, but do we know it's true? Do we have any evidence that the people injured in home repairs were hurt primarily because of poor Internet instructions, rather than because of any one of a number of other possible causes? Can we say with absolutely certainty that, of all possible causes, the bad instructions on the Internet were the prime culprit in hurting all these people? We cannot. The low quality of the Internet instructions could be the primary culprit, but we don't know for sure that it is.

You see, the text used a clever juxtaposition to suggest something, to draw the reader into an assumption. That's not the same as an inference. On the GMAT, an inference is something you know with bedrock certainty, as an inescapable conclusion of what appears in the text.

Does all this make sense?
Mike
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Hello Mike,

Thanks for the explanation, I now understand why C is a contender.

Had a quick question that I wanted to put across to you..

Isn't the sale of something that is mentioned to be free in the premise a little weird to accept while choosing the answer? I disregarded C for this very reason.

Dear aarchak,
I'm happy to help.

The prompt argument says:
The rise in free, do-it-yourself instructions on the Internet for home repairs has led to a decrease in revenue for home service technicians and an increase in the number of injuries caused by people who have attempted home repairs themselves. Unfortunately, not all of the do-it-yourself instructions on the Internet are written as well as they should be.

That lets us know that some of the online do-it-yourself instructions, but we don't know that all of them are free. The fact that some are free would make it even harder to sell the ones that aren't free.

Does this make sense?
Mike
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Hi,

Thanks for explaining why C is correct . I understand the point why C seems to be correct answer. But, I have a slightly different doubt:
According to me, Inference can be made only from the given argument (and we can not assume any other external info).
So, basically an inference is something which we can PRETHINK also by analyzing the given text only.

But in option C , it provides external info that is 'online do-it-yourself home repair instructions are sold by home service technicians', which is never mentioned in the argument. So this introduces external info , which makes this inference incorrect.

The argument should contain that home service technicians also sale online do-it-yourself home repair instructions in addition to doing service at home . Then only this ans would be correct.

Please let me know if i am wrong!!!!!!!

Dear mayankmalik01,
I'm happy to respond.

First of all, with all due respect, I want to point out a grammar flaw in what you wrote. The word "sale" is a noun, and the word "sell" is a verb. Does this make sense?

I would say that this argument doesn't bring in too much new information in the answer choice. I believe the GMAT itself does this some times. An inference should be a conclusion completely obvious from the prompt, but it may involve a detail not mentioned in the prompt.

Here, we don't know whether home service technicians sold online do-it-yourself home repair instructions. Maybe they did and maybe they didn't. We don't know. Choice (C) says: "The overall sale of online do-it-yourself home repair instructions by home service technicians has not been equal to the loss of revenue the technicians have incurred due to free offerings of this sort of material." Well, if there were absolutely no online sales, then the revenue from those sales would be zero, and they certainly would not be equal to money lost. The answer choice is perfectly correct even if the home service technicians sold nothing online.
We are told about a "decrease in revenue for home service technicians." We know for a fact that those folks have had a net decline in revenue. They have definitely lost revenue from service calls to people's homes. If they have had a net decline in revenue, that means whatever gain in revenue they have had, from any source, is not as big as what they lost because of the online offerings. The fact that the new source of revenue was not explicitly mentioned in the prompt is not a big issue here, because we already know that any source of revenue would not be equal to what they lost, because they had a net decline in revenue. The identity of the source of income is logically less important then the fact that it is a source of income. Think about if (C) were:
"Any additional source of revenue has not been equal to the loss of revenue the technicians have incurred due to free offerings of this sort of material." That is undeniably correct from the prompt. All they did was remove the generic "any source of revenue" and plug in a specific source of revenue. This change adds distracting detail but does not change anything in the fundamental logical relationships.

The PRETHINK rule that you cite is a bit too fundamentalist. It's perfectly fine for the OA to introduce a new idea if the logical framework for the idea is already treated in the prompt argument. Does this distinction make sense?

Mike
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But must be true means that it must be from the passage

or we can make assumptions outside also?

Because, from the passage, we can inferred that some people attempeted DIYing by reading the free instructions, and these people got injured

Dear peterparker123
I'm happy to respond.

Here's a blog article on this topic you may find helpful:
https://magoosh.com/gmat/2013/gmat-criti ... inference/

An inference is something that MUST be true based on the passage. We absolutely cannot make new assumptions or bring in completely outside information --- that's always wrong. BUT, and this is the tricky thing that people sometimes overlook: you do have to make strict logical deductions from the information in the passage. Those deductions can lead to statements that you would have predicted.

What you say as an inference --- "some people attempted DIYing by reading the free instructions, and these people got injured" --- yes, that would be an inference, but by GMAT standards, that's far too easy. The passage more or less hands that to you on a silver platter. That's not an example of the kind of inference the GMAT would ask you to make. Answer choice (C), the OA, is much more like a GMAT-like inference. Choice (C) is not something explicitly stated, not something we would be likely to predict from reading the passage, but when we get to (C) and think about it, we realize that it absolutely has to be true, given what is stated in the passage. That's much more typical of what the GMAT will demand.

Does all this make sense?
Mike
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Mike, can you write a little about what's wrong with option A?

Dear ronr34,
I'm happy to respond, my friend.

Here's the prompt again:
The rise in free, do-it-yourself instructions on the Internet for home repairs has led to a decrease in revenue for home service technicians and an increase in the number of injuries caused by people who have attempted home repairs themselves. Unfortunately, not all of the do-it-yourself instructions on the Internet are written as well as they should be.

Which of the following can be inferred from the argument above?

Here's option (A):
(A) The number of people who are not home repair technicians and who have been injured while attempting home repairs has increased.

Now, the very important thing to remember about a GMAT CR inference question --- we are NOT looking for something that COULD be true, that plausibly would be true, or even for something that is probably true. None of those meet the mark. We are looking for something that absolutely, without a doubt, MUST be true, something that absolutely couldn't not be true, based on the information in the prompt. See this article for a longer discussion:
https://magoosh.com/gmat/2013/gmat-criti ... inference/

On a GMAT CR question, there will be one correct answer that absolutely, non-negotiably, MUST be true, and then four other wrong answers that are all plausible, all things that we reasonably imagine could be true; in fact, for some of them, it may requires some very special conditions for them not to be true. The point is, though --- as long as it is even remotely possible that a statement is not true, then it is not a solid inference from the GMAT's point of view.

Could (A) be false?
We absolutely know from the prompt argument that the number of injuries has increased --- does this mean a larger number of people are getting injured, as (A) suggests, or does it mean the same unskilled people who have injured themselves before haven't learned and are injuring themselves again in their continued bumbling attempts at home repair? In other words, the number of injuries could increase without a corresponding increase in the total number of individuals who have been injured. Is this likely? I don't know, but that doesn't matter. It's possible for (A) to be false, given the information in the prompt, and as soon as we can imagine that (A) could possibly be false, it is absolutely disqualified as a GMAT CR inference.

Does all this make sense?
Mike
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