PrepTest 114, Section 1, Question 22
Damming the Merv River would provide irrigation for(62 more words not shown)
The reasoning in the argument(11 more words not shown)
- ADisease-causing bacteria in(35 more words not shown)
- BIncreasing the price(35 more words not shown)
- CA new highway(41 more words not shown)
- DDoctors can prescribe(35 more words not shown)
- EA certain chemical(44 more words not shown)
Reading the argument
Helping the farms upstream isn't enough if the farms downstream lose even more. As soon as the dam's irrigation benefit appears, I want to know what happens on the other side. The argument answers that question: less and poorer-quality water would reduce productivity downstream. Then it gives the comparison we need. The downstream loss would exceed the upstream gain.
Suppose the dam adds four units of agricultural output upstream but costs five units downstream. The region loses one unit overall. Those numbers are just an illustration, but they show why the conclusion makes sense. The author has supplied the relative size of the effects instead of assuming that one outweighs the other.
What we’re looking for
For the parallel question, look for an action with a benefit and a larger harm measured against that same benefit, followed by a conclusion that there is no overall improvement. We need the whole comparison, not merely an answer mentioning both an upside and a downside.
Working the answers
- A
Overcooking improves safety but worsens taste, and the argument chooses safety because it matters more. That is a judgment about which of two different goals should take priority. The dam argument compares gains and losses in the same outcome—agricultural productivity—and concludes that there is no overall gain. A also recommends the action instead of denying an overall improvement.
- B
This tells us private callers will be discouraged and businesses make most calls. It doesn't compare a gain caused by the price increase with a larger loss, then combine the two. The conclusion also concerns profits, while the stated change concerns calling behavior. Simply telling us which customers make most calls doesn't supply the original's offsetting-effects calculation.
- CCorrect
The highway is the dam: the proposed change. Time saved on the highway is the productivity gained upstream. Extra delays within the city are the productivity lost downstream. We're told those delays more than offset the savings, just as the agricultural loss exceeds the gain.
The conclusion stays with the same overall measure: the suburban commuters' total commuting time won't improve. This isn't a comparison of suburban commuters' benefits with a separate group of city residents' losses. It's the savings and delays within the commuters' whole trip, which together produce no net time saving.
- D
This compares two ways to address an illness and recommends the less costly one when rest can cure it. It doesn't show that taking one action creates a benefit that is outweighed by a larger loss of the same kind. The fact that antibiotics have a cost isn't enough to reproduce the dam argument's structure.
- E
The first part is close: the chemical protects tomatoes while damaging other plants more severely. But the conclusion changes the task. It identifies the only kind of garden that can benefit, rather than concluding that a particular garden gains no overall benefit.
To make the original conclude that way, it would need to say something like, “The only rivers worth damming are those without affected farmland downstream.” It doesn't. It concludes that this dam yields no overall productivity gain in this region. E's restriction on which situations can benefit isn't that conclusion.
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