Four randomly chosen market research companies each produced

Question

Four randomly chosen market research companies each produced population estimated for three middle-sized cities; the estimates of each company were then compared with those of the other companies. Two of the cities had relatively stable populations, and for them estimates of current population and of projected population in five years varied little from company to company. However, for the third city, which was growing rapidly, estimates varied greatly from company to company.

Which one of the following, if true, would best help explain why estimates of the current population of the rapidly growing city varied more than did current population estimates for the two other cities?

(A) Population changes over time are more uniform from one district to another in the rapidly growing city than in the two other cities.

(B) The population of the rapidly growing city is increasing largely as a result of a high birth rate.

(C) The population of the rapidly growing city has a lower average age than the populations of either of the two other cities.

(D) All population estimates of the rapidly growing city were produced first by estimating the current populations of the city’s districts and then by adding those estimates.

(E) Whereas the companies used different methods for estimating the current population of the rapidly growing city, the companies used the same method for the two other cities.

Source: LSAT

DAVEexamPAL · Answer

The answer is (E).

We are asked to explain a difference in  outcomes , and thus we will look for an answer which describes a difference in  conditions :  (E) does just that: different measuring methods were used.

As always, we can also approach this question by talking each answer and eliminating, though this may take more time:

(A) Population changes over time are more uniform from one district to another in the rapidly growing city than in the two other cities.  On the contrary - this would suggest the rapidly growing city's estimates would be more consistent, not less

(B) The population of the rapidly growing city is increasing largely as a result of a high birth rate. Not clear why this is relevant

(C) The population of the rapidly growing city has a lower average age than the populations of either of the two other cities.  Not clear why this is relevant

(D) All population estimates of the rapidly growing city were produced first by estimating the current populations of the city’s districts and then by adding those estimates.   On the contrary - this highlight a similarity in the methods, which would suggest a similarity in the results

(E) Whereas the companies used different methods for estimating the current population of the rapidly growing city, the companies used the same method for the two other cities.  Yes - if they used different methods, makes sense they would get different results

lavanya.18 · Answer

E is the best way to explain this paradox, because if the companies used different methods for the third city, then it makes sense that they would get different results.

Correct Answer: E

unraveled · Answer

Four randomly chosen market research companies each produced population estimated for three middle-sized cities; the estimates of each company were then compared with those of the other companies. Two of the cities had relatively stable populations, and for them estimates of current population and of projected population in five years varied little from company to company.  However, for the third city, which was growing rapidly, estimates varied greatly from company to company .

Which one of the following, if true, would best help explain why estimates of the current population of the rapidly growing city varied more than did current population estimates for the two other cities?

(A) Population changes over time are  more uniform from one district to another  in the rapidly growing city than in the two other cities. - WRONG. Why it varied for rapidly growing city is not answered. Uniformity between two cities is fine but it doesn't explain why we are seeking.

(B) The population of the rapidly growing city is  increasing largely  as a result of a  high birth rate . - WRONG. Irrelevant.

(C) The population of the rapidly growing city has a  lower average age than  the populations of either of the two other cities. - WRONG. Like B this one too is irrelevant.

(D) All population estimates of the rapidly growing city were produced  first by estimating the current populations of the city’s districts and then by adding those estimates . - WRONG. Again no explanation to why it varies.

(E) Whereas the  companies used different methods for estimating the current population of the rapidly growing city , the companies used the same method for the two other cities. - CORRECT. The method might be having factor that lead to higher Standard deviation.

Answer E.

Four randomly chosen market research companies each produced

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Four randomly chosen market research companies each produced

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