A recent study released by the government examined geographic patterns

Question

A recent study released by the government examined geographic patterns among energy use in the U.S. According to the study's results, monthly energy bills for homeowners in the eastern part of the country are higher on average than those for homeowners residing in the western U.S. Based on this finding, the study's authors concluded that homeowners in the eastern part of the country use more energy than those in the west.

Which of the following is an important assumption for the conclusion above to be true?

A. Fluctuations in monthly energy bills (e.g., based on weather) were similar among the eastern and western homeowners studied.
B. The unit cost of energy in the eastern and western parts of the country is the same. 
C. Monthly energy costs for renters in the eastern part of the U.S. are higher than those for renters in the west.
D. The average sizes of homes in the eastern and western parts of the country are significantly different.
E. Sources of energy (e.g., electricity, natural gas, etc.) used are proportionately similar in the eastern and western U.S.

Sloth45 · Answer

Question type: Assumption

Premise: Average energy bills for homeowners in Eastern part is higher than those for homeowners in Western part.

Conclusion: Homeowners in eastern part use more energy than those in the west.

We can use the Negation technique to see if the premise and conclusion holds true for the given statements:

A. Change in energy bills in East and West are different ( if one rises by $100, another falls by $100 and vv).  It has nothing to do with the conclusion.

B. Unit cost of energy is different. If the unit cost of energy is higher in eastern part, average energy bills will be obviously higher even if they are using less 
 energy. This statement hurts the argument. So, this is the assumption.

C. Monthly energy costs for renters are lower in eastern part than those for renters in west. It doesn't hurt the conclusion.

D. The average size of home in east and west are same.  It doesn't hurt the conclusion.

E.Sources of energy used are different.  It doesn't hurt the conclusion.

G780MAT · Answer

I doubt with option C, please can anyone explain better?

guddo · Answer

A recent study released by the government examined geographic patterns among energy use in the U.S. According to the study's results, monthly energy bills for homeowners in the eastern part of the country are higher on average than those for homeowners residing in the western U.S. Based on this finding, the study's authors concluded that homeowners in the eastern part of the country use more energy than those in the west. 
 
Which of the following is an important assumption for the conclusion above to be true?

The argument moves from higher energy bills to greater energy use.  The key assumption  is that  the higher bills are not simply caused by higher prices per unit of energy in the East .

(A) Fluctuations in monthly energy bills (e.g., based on weather) were similar among the eastern and western homeowners studied.

Incorrect. Seasonal fluctuations do not have to be identical for the conclusion to hold.

(B) The unit cost of energy in the eastern and western parts of the country is the same.

Correct.   If energy costs more per unit in the East, eastern homeowners could have higher bills even while using the same amount of energy, or even less energy. The argument therefore needs to rule out that possibility.

(C) Monthly energy costs for renters in the eastern part of the U.S. are higher than those for renters in the west.

Incorrect. The argument concerns homeowners, not renters.

(D) The average sizes of homes in the eastern and western parts of the country are significantly different.

Incorrect. Different home sizes might help explain different energy use, but the conclusion does not require homes to differ in size.

(E) Sources of energy (e.g., electricity, natural gas, etc.) used are proportionately similar in the eastern and western U.S.

Incorrect. The regions could use different energy sources and still differ in total energy use. What matters is whether higher bills actually reflect greater quantity consumed.

Answer: (B)

egmat · Answer

Hi G780MAT,

Good question. The quickest way to see why  C  fails is to check what the conclusion is actually about.

The author concludes something about  homeowners :  "homeowners in the eastern part of the country use more energy than those in the west."  Every piece of the argument - the premise about higher monthly bills and the conclusion about higher usage - is about  homeowners .

Now look at C:  "Monthly energy costs for  renters  in the eastern part of the U.S. are higher than those for renters in the west."

C switches the group to  renters . That's the slip to catch - the conclusion never mentions renters, so anything about them lands  outside the scope  of the argument.

Here's the test for an assumption: the conclusion must  depend  on it. Ask yourself - does the claim "eastern homeowners use more energy" need renters' bills to behave a certain way?

- If renters' costs were higher in the east - the homeowner conclusion is unaffected.
- If renters' costs were  lower  in the east - the homeowner conclusion is  still  unaffected.

Since the conclusion holds up either way, C is  not  required. It's a true-or-false statement about a different group, doing nothing to the homeowner link. Contrast that with  B  (unit cost of energy is the same): negate it - if energy costs more per unit in the east - and the bills-to-usage jump collapses. That dependence is exactly what makes B the assumption and C irrelevant.

A quick habit to lock this in:  whenever a choice quietly swaps the subject the conclusion is about - homeowners - renters, one city - the whole country - flag it. A fact about a group the argument never discusses can't be something the argument  needs .

Answer: B

A recent study released by the government examined geographic patterns

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