PrepTest 101, Section 3, Question 21
The amount of electricity consumed in Millville on(45 more words not shown)
Which one of the following(15 more words not shown)
- AThe amount of(57 more words not shown)
- BThe number of(51 more words not shown)
- CThe number of(46 more words not shown)
- DThe fees paid(50 more words not shown)
- EThe number of(58 more words not shown)
Reading the argument
Would humidity really determine electricity use so neatly? I'd normally wonder about temperature, too. But the passage gives us a direct proportion as a premise. We should accept that relationship and see what follows from it, rather than replace it with our own account of air conditioning.
Under that rule, higher humidity goes with higher electricity use. This August has a higher average peak humidity than last August, so it has higher average daily consumption. Both Augusts have the same number of days, so the higher daily average also gives us a higher monthly total. That conclusion makes sense given the stated relationship.
What we’re looking for
We're looking for the same reasoning in another setting: two quantities rise together in a fixed proportion; the amount of one increased; therefore the amount of the other increased. Keep track of which two quantities the rule actually connects. A change in something related to them wouldn't necessarily do the job.
Working the answers
- ACorrect
The amount of art supplies corresponds to electricity use, and the number of students corresponds to humidity. Each class is the smaller unit being considered, as each day is in the original. The rule connects the supplies used in a class to the students in that class. Across the institute's twenty-five classes, total enrollment increased, so total supplies used increased too.
The original tells us about an increase in average humidity across the days of August; A directly gives an increase in overall enrollment across the classes. Both establish more of the quantity to which consumption is proportional. The same fixed relationship supports the increase in consumption.
- B
The rule connects painting courses to enrollment, but the conclusion compares painting courses with sculpture courses. Nothing establishes which number is larger. The institute could offer two painting courses and twenty sculpture courses while satisfying the stated relationships. We need an increase in one quantity leading to an increase in its partner, not an unsupported comparison with a third quantity.
- C
This moves from a relationship to a claim about what the institute must do to achieve a goal. It doesn't tell us that advertising actually increased and then conclude that new enrollment increased. That observed-change step is central to the original. Merely mentioning a direct proportion doesn't make these arguments work the same way.
- D
The fees depend on how many classes students take, not simply on how many students attend. Imagine enrollment rises from one hundred students taking two classes each to two hundred students taking one class each. There are more students, but still two hundred class enrollments. With the same fee per class, total fees would stay the same. D changes the wrong quantity and then assumes that the amount connected to fees must have increased too.
- E
Here the number of instructors is linked separately to classes and students, and the conclusion connects classes with students through that shared relationship. It doesn't give an increase in one quantity and infer an increase in another. Its task is to establish a relationship between two quantities, rather than apply an existing relationship to a change.
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