Logical Reasoning

PT102 · S3 · Q18 In the past decade, a decreasing

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In the past decade, a decreasing percentage of money spent on treating disease X went to pay for standard methods of treatment, which are known to be effective though they are expensive and painful.

Conclusion

Less money is being spent on effective treatments of X now than ten years ago.

Evidence

Only the standard treatments for X are effective, and a decreasing percentage of money being spent on treatments of X now than ten years ago.

Evaluate

Let's say we run a business and every month we spend $2000 on advertising -- $1000 is newspaper ads and $1000 is Facebook ads.

We currently spend 50% of our advertising budget on newspaper ads.

If we decide to experiment and add another $1000 into the Facebook ads category, then we'd be spending $1000 on newspaper and $2000 on Facebook.

That means we now spend 33.3% of our ad dollars on newspaper ads.

We now spend a decreased percentage of our ad budget on newspaper ads, but do we spend less money on newspaper ads?

No, we spend the same amount of money.

The author of this argument is confusing those two things.

The author is making the move from,

But we just showed that you can spend a lower percentage on something without spending less money on it.

If we were trying to contradict the author's conclusion, we could say,

Goal

The only wiggle room to this argument is if the overall amount of money spent on treating disease X has gone up (that's the only way that a lower % of a total could still end up equaling at least as big a number as before).

i.e. 50% of a $2000 ad budget was the same as 33.3% of a $3000 ad budget

So to lock in the author's conclusion, we want to hear that the total is the same, or that it's lower than before.

18.

Which one of the following, if assumed, allows the conclusion above to be properly drawn?

Varieties of disease X requiring
Unrelated to Goal
Since this argument just hinges on whether "lower % of total spending = less spending", this answer isn't telling us something that could prove the conclusion. It strengthens the idea that we're spending less money, but it definitely doesn't 100% prove it.
4% picked this
Nonstandard methods of treating disease
Unrelated to Conclusion
The conclusion is about how much money we're spending on effective (i.e. standard) treatments, so hearing about how much nonstandard treatments cost has nothing to do with how much we're spending on effective treatments.
7% picked this
Of total medical expenditures, the
Out of Scope: total medical
We don't care what % of a nation's total health care expenditures is related to X. We just care whether the actual amount of money being spent to treat disease X has gone up, stayed the same, or gone down.
4% picked this
Most of the money spent
No Impact
It doesn't really matter to this argument whether standard or nonstandard treatments claim more or less than 50% of the budget. This argument is all about the relative movement of spending on effective treatments over time. Whether it started out above or below 50% of total spending, it could still be less now than it was ten years ago. So finding out that standard (effective) treatments are less than 50% of total spending sounds kinda strengthen-ish, but it doesn't mathematically prove the conclusion.
39% picked this
Correct
The total amount of money
Why this is right
This mathematically proves the conclusion. A lower percentage of money is spent on effective (standard) treatments nowadays. If the total amount of money being spent on treatments nowadays is lower than before, then we're definitely spending less money on effective (standard) treatments. A smaller percentage of a smaller total definitely comes out to a smaller actual number. Here's an example of a percentage and a total going down, which is guaranteed to result in a smaller actual number. Total % on eff Amt on eff 10 yrs ago $100k 40% $40k now $90k 30% $27k
Skill tested: Sufficient Assumption · how this choice captures the argument's function is the move to repeat next time.
46% picked this

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