PrepTest 139, Section 1, Question 4
Chemical-company employee: A conservation group's study of the(41 more words not shown)
Which one of the following(8 more words not shown)
- AThe conservation group(11 more words not shown)
- BThe employee's company(19 more words not shown)
- CThe total pollution(18 more words not shown)
- DThe four other(23 more words not shown)
- EThere is no(15 more words not shown)
Reading the argument
How much of that 60 percent is ours?
Five companies together produce a large share of the pollution. That doesn't tell us whether this employee's company contributes a large share. The other four might be doing nearly all the polluting.
For example, suppose those four account for 59.9 percent of the total, while the employee's company accounts for just 0.1 percent. The other twenty-five companies could divide the remaining 40 percent evenly and each produce more than the employee's company. We'd have exactly the reported 60 percent for the five-company group, yet this company would be a relatively small polluter.
There's a further question about the sample. What if these are the thirty cleanest small chemical companies? A comparison within that group might not tell us much about small chemical companies generally. But the first gap comes even earlier: we haven't isolated this company's contribution from the other four companies' contributions.
What we’re looking for
For a required assumption, I'd look for something the employee needs to rule out that problem. We don't need an equal five-way split. We do need the other four companies not to account for nearly the whole 60 percent by themselves.
Working the answers
- A
A conservation group could dislike the chemical industry and report its pollution accurately. We can accept the study's numbers and still question the employee's move from five companies together to this one company. The group's attitude doesn't fix that move.
- B
The argument compares how much pollution companies release, not why their processes produce it. The employee's company might make chemicals that naturally generate more pollutants and still release more pollutants overall. It might also use cleaner processes but have other reasons for a high total. B isn't required to establish the comparison.
- C
Large companies could produce far more pollution than all the small companies combined. That would tell us nothing about where this company ranks among companies similar to it in size. The conclusion makes that smaller-company comparison.
- DCorrect
If the other four companies account for nearly all the 60 percent, the employee's company could contribute very little. D rules out the possibility illustrated above. That is a needed protection for the employee's use of the group total; it doesn't require equal contributions or settle every other question about the comparison.
- E
The other twenty-five companies don't all have to release similar amounts. The employee's company could exceed most of them even if some release much more pollution than others. Making those twenty-five equal also wouldn't solve our problem: this company's own share of the 60 percent could still be tiny.
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