Q14 - Thirty years ago, the percentage

[geverett]

I got this one wrong, but now understand the error of my ways. Here it is:

Stimulus:

Premise 1: The percentage of British people who vacationed abroad 30 years ago is much smaller than the percentage of people who vacation abroad now.

Conclusion: British people must have more money to spend on vacation today than they did 30 years ago.

So the author assumes that based on an increase in the percentage of British people who take vacations abroad that it is safe to conclude that British people have more money on average to spend on vacations.

The core would look like this:

Increase in % of British British people must have
people vacationing abroad -----> more money to spend on
from 30 years ago vacations than 30 years ago.

So we can see that it's a pretty big assumption to make that British people taking more vacations today must mean they have more money to spend on vacations abroad. Perhaps they don't have more money to spend, but instead have priorities that have changed which have made vacations abroad more important than they were in the past. Or perhaps British people are actually going into debt more than they have in the past. It could be many other things, but the question is asking us for a necessary assumption that the argument requires in order to be valid. Let's check out the answer choices:

(A) This asks us to examine a hypothetical based on what British people might have done 30 years ago if foreign travel had been less expensive. If anything, based on the assumption the author is making, had the cost of travel been less 30 years ago then the British people would have traveled more perhaps. However, that would require us having more information on whether or not the lower cost of travel was sufficient to allow more people to afford travel abroad. We don't have that information and so this answer choice is wrong.
(B) This is about "travel to Britain" whereas the stimulus is about "British people traveling abroad". Out of scope. Get rid of it.
(C) This is trying to force us to infer something that you just cannot infer. We know that the percentage of British people vacationing abroad 30 years ago was lower, but we cannot infer from that information that as a result they spent more money on "domestic vacations". Unsupported. Get rid of it.
(D) This is it. I originally did not choose it, because I saw our conclusion focusing on British people today that vacation abroad more while this answer choice talks about British people from 30 years ago who vacation abroad less. However, this answer choice is relevant as it sets up a conditional that must be the case in order for the authors argument to be true. Here is what what the conditional and its contrapositive looks like:

If more Brits from 30 More Brits from 30
years ago had enough ------> years ago would have
money to vacation vacationed abroad
abroad

The contrapositive of this clearly reveals that this must be the case in order for the authors argument to hold water. In essence the contrapositive says:

More Brits from therefore More Brits did not enough
30 years ago did ----> money to vacation abroad
not vacation abroad

Please feel free to ask more questions if the necessity of this statement to the author's argument is not apparent.

(E) This answer choice is just plain wrong, but deceitful in the time crunch of the test. This answer choice talks about British people being "wealthier" whereas our argument makes no mention of an increase in overall wealth. The stimulus only makes an argument about having more money to spend on average for vacations abroad. These are two very different things. Feel free to ask if the difference is not readily apparent. Out of scope. Get rid of it.

[demetri.blaisdell]

Great explanation! It's clear you really understand the problem. I'm going to do a quick summary for others who are confused. Diagram of argument core:

Percentage of British people who travel has increased --> Average amount of money British people have to spend on travel has increased

The gap is an assumption: Amount of money available for travel is the factor that determines how much the British travel. What if they are/were just afraid of flying? (D) is a necessary assumption: if money weren't an obstacle, more British would have traveled 30 years ago. If this weren't true (negation test), percentage of travelers would be a bad way of determining how much money is in travel budgets.

(A) is a premise booster. We already know it was/is expensive to travel out of Britain.

(B) is way out of scope. We only care about the British traveling abroad.

(C) sounds believable but is also out of scope. We only care about their ability to travel abroad. Domestic travel won't affect the argument.

(E) is out of scope. The argument only concludes that the British have more money to travel with not that they are wealthier over all. It's also the incorrect causal claim. We want vacation more --> have more vacation money not have more money --> more vacation money.

Your explanation was great, I just wanted to put a shorter version for the LSAT student on the go! A few of my explanations of wrong answers are a little different, also, so perhaps check them out if you have time.

Demetri

[ysabel.jurado]

Hi,

So when we are negating answer (D) it would go:

1. If more of the British people of 30 years ago did not have enough money to vacation abroad, more would have done so

or

2. If more of the British people of 30 years ago did not have enough money to vacation abroad, more would not have done so.

I get confused with the negation test when there are multiple clauses and verbs in the answer. Do we negate both or simple one will be enough?

Thnaks!!

[austindyoung]

Hi,

So when we are negating answer (D) it would go:

1. If more of the British people of 30 years ago did not have enough money to vacation abroad, more would have done so

or

2. If more of the British people of 30 years ago did not have enough money to vacation abroad, more would not have done so.

I get confused with the negation test when there are multiple clauses and verbs in the answer. Do we negate both or simple one will be enough?

Thnaks!!

Negation of (D) is: If more of the British people of 30 years ago had had enough money to vacation abroad, more would NOT have done so.

[jrnlsn.nelson]

The explanations provided thus far are interesting. I'd like to chime in because my line of reasoning behind why (D) is the correct answer is not like any of the previous explanations. I also think that my line of reasoning is more accurate. I only missed 1 problem in this LR section (credibility boost maybe?).

Anyways, I saw this problem as testing "cause and effect reasoning." The conclusion is:

"Therefore, British people must have, on average, more money to spend on vacations now than they did 30 years ago."

And the first sentence (i.e. the premise) says:

"Thirty years ago, the percentage of the British people who vacationed in foreign countries was very small compared with the large percentage of the British population who travel abroad for vacations now."

So, in order to visualize this I thought to myself: "So the stimulus is saying this: 30 years ago 20 percent of the British population traveled abroad, whereas now 40 percent of the British population travels abroad (the percentages I chose are arbitrary). And the conclusion is saying that the the reason for this increase in travel (in other words -- the CAUSE of this increase in travel) is because the British people have more money to spend now than they did 30 years ago. Thus, the LSAT test makers want us to infer that the author of the stimulus is assuming that an increase in money caused an increase in travel."

Cause = Increase in money to spend on travel

Effect = Increased travel abroad

Now, whenever I see a stimulus with causal reasoning in the conclusion together with an assumption type question I immediately begin to look for an answer choice that affirms the causal reasoning that the author put forward. This is a classic LSAT causal reasoning strategy (I'm pretty sure Manhattan LSAT teaches this strategy). Anyways, (D) affirms the causal reasoning laid out in the stimulus.

(D) says: "If more of the British people of 30 years ago had had enough money to vacation abroad, more would have done so."

Causal reasoning on the LSAT is presented in a unique way. Anytime an author of a stimulus puts forward causal reasoning in the conclusion, they believe that the specified cause of the effect is the ONLY cause of the effect and that whenever this cause is present that the effect will ALWAYS occur. This point is key and took me a while to wrap my head around. But, after doing plenty of PTs and seeing cause and effect reasoning a lot and applying this strategy to questions types with causal reasoning I now consistently get them correct.

Now look at (D) again, it's essentially saying that if Britain's population had more money 30 years ago to travel abroad they would have traveled abroad more. This is exactly what we're looking for. If this seems awkward to you, try applying this strategy to future questions with causal reasoning and see what happens. My bet is that you will start to see the correct answers much more easily, and simultaneously (and perhaps more importantly) be able to eliminate the incorrect answers more effectively.

[ajay12121212]

Hi jrnlsn.nelson,
Your way of identifying the problem as a causal reasoning problem looks good to me.
I would like to develop this approach.
Can you please share some more examples/links/explanations by the means of which such thought can be developed ?
Thanks,

[LauraS737]

We want vacation more --> have more vacation money not have more money --> more vacation money. Demetri

Hi,
I'm a little confused because isn't the author assuming that people having more money to travel as a reason for the increase in travel? Hence, wouldn't the causal claim be: More money --> more travel?

Where's my reasoning going wrong?

[Emmeline Ndongue]

We want vacation more --> have more vacation money not have more money --> more vacation money. Demetri

Hi,
I'm a little confused because isn't the author assuming that people having more money to travel as a reason for the increase in travel? Hence, wouldn't the causal claim be: More money --> more travel?

Where's my reasoning going wrong?

it is. I think it should be the other way around. she probably made a mistake. "More money to spend on travel --> travel more" this is the assumption being made! (because out of one's own priority, even if one has enough money to travel abroad, they can choose not to, and spend the money on sth else!

[SJK493]

The premise refers to percentages (percentage of British people), while the conclusion refers to numbers (more money to spend). Wouldn't it be flawed to make a comparison of the percentage of British people now and thirty years ago, and then proceed with something about money spent? How would you deal with the numbers and percentages in this question?