A survey of address changes filed with post offices and driver’s

Question

A survey of address changes filed with post offices and driver’s license bureaus over the last ten years has established that households moving out of the city of Weston outnumbered households moving into the city two to one. Therefore, we can expect that next year’s census, which counts all residents regardless of age, will show that the population of Weston has declined since the last census ten years ago.

Which one of the following, if true, most helps strengthen the argument?

(A) Within the past decade many people both moved into the city and also moved out of it.
(B) Over the past century any census of Weston showing a population loss was followed ten years later by a census showing a population gain.
(C) Many people moving into Weston failed to notify either the post office or the driver’s license bureau that they had moved to the city.
(D) Most adults moving out of Weston were parents who had children living with them, whereas most adults remaining in or moving into the city were older people who lived alone.
(E) Most people moving out of Weston were young adults who were hoping to begin a career elsewhere, whereas most adults remaining in or moving into the city had long-standing jobs in the city.

Skywalker18 · Answer

A survey of address changes filed with post offices and driver’s license bureaus over the last ten years has established that households moving out of the city of Weston outnumbered households moving into the city two to one. Therefore, we can expect that next year’s census, which counts all residents regardless of age, will show that the population of Weston has declined since the last census ten years ago.

Type- strengthen 
Boil it down- we can expect that next year’s census,  which counts all residents regardless of age , will show that the population of Weston has declined since the last census ten years ago.

(A) Within the past decade many people both moved into the city and also moved out of it. - incorrect - we already know that more people moved out
(B) Over the past century any census of Weston showing a population loss was followed ten years later by a census showing a population gain. - Irrelevant- we are talking about a decade whereas this choice talks about a century; at best this choice is a mild weakener
(C) Many people moving into Weston failed to notify either the post office or the driver’s license bureau that they had moved to the city. - weakens - so the number of people moving into Weston may be underreported and the ACTUAL number is more than the reported number
(D) Most adults moving out of Weston were parents who had children living with them, whereas most adults remaining in or moving into the city were older people who lived alone. - Correct
Majority of people moving out are families while most people who stayed or moved in are singles(Children would not have their own postal address and driving license). Therefore, the census will show that the population has declined
for example - 2 families moved out and each of the family has 4 members 
1 single person moved in. Although, the household moving out to moving in ratio is 2:1, the ACTUAL number of people moving out to moving in ratio is 8:1

(E) Most people moving out of Weston were young adults who were hoping to begin a career elsewhere, whereas most adults remaining in or moving into the city had long-standing jobs in the city. - Irrelevant

Answer D

Abhishek009 · Answer

Outflow > Inflow 
Conclusion : Result of census will be lesser

Prethinking : What about Population growth in the city , what if the pop grows faster ?? Can it still have less population compared to last census...

Non but (D) flows along our pre thinking logic/lines, hence Answer must be (D)

unraveled · Answer

A survey of address changes filed with post offices and driver’s license bureaus over the last ten years has established that households moving out of the city of Weston outnumbered households moving into the city two to one. Therefore, we can expect that next year’s census, which counts all residents regardless of age, will show that the population of Weston has declined since the last census ten years ago.

Which one of the following, if true, most helps strengthen the argument?

(A) Within the past decade many people both moved into the city and also moved out of it. - WRONG. Goes nowhere i.e. no direction is clear - weakens or strengthens it is not sure.
(B) Over the past century any census of Weston showing a population loss was followed ten years later by a census showing a population gain. - WRONG. Weakens somewhat if at all it does anything.
(C) Many people moving into Weston failed to notify either the post office or the driver’s license bureau that they had moved to the city. - WRONG. Weakens actually.
(D) Most adults moving out of Weston were parents who had children living with them, whereas most adults remaining in or moving into the city were older people who lived alone. - CORRECT. More move out than those move in.
(E) Most people moving out of Weston were young adults who were hoping to begin a career elsewhere, whereas most adults remaining in or moving into the city had long-standing jobs in the city. - WRONG. Only a portion(adults) is considered and that too we are not sure whether those moving out equal those moving in. Even if it is so it doesn't help at all.
 
Answer D.

yc168 · Answer

OE for reference:

Overview:  
The argument begins with the premise that a survey of address changes shows that over the last ten years twice as many households moved out of Weston as moved in. The argument concludes that the number of people living in Weston has decreased over the last ten years. You are asked to find a statement that strengthens this argument.

Notice that the premise of the argument is about how many   households   have moved into and left Weston, while the conclusion is about a change in the number of   people   living in Weston. It's important to remember that not all households are the same size.

The Correct Answer:

D  (D) says that most of the households staying in or moving into Weston were single people and most of those moving out were families with children. This makes it very likely that the households moving out were, on average, larger than those moving in. Since (D) gives us more reason to think that the population has declined, it strengthens the argument.

The Incorrect Answer Choices:

A  (A) says that many people moved into Weston and then out (or vice versa) within the last ten years. This does not imply anything about the total number of people who moved into Weston or out of Weston. This would have no net effect on the population of Weston in that period, so it neither strengthens the argument nor weakens it.

B  (B) says that over the past century any census of Weston showing a population loss was followed ten years later by a census showing a population gain. Even if we can expect this trend to continue, we don't know what the last census showed. So (B) is not relevant to the argument since it gives us no basis for making an inference about the next census.

C  The premise of the argument uses data from post offices and driver's license bureaus to establish that more households moved out of Weston than moved in. (C) says that many of the people who moved in didn’t tell the post office or the driver's license bureau, suggesting that the number of households moving in was undercounted. This would make the argument's conclusion that the number of people living in Weston has decreased less likely to be true. So (C) weakens rather than strengthens the argument.

E  (E) tells us about the different career situations of those moving out of Weston and those moving in. However, those facts don’t tell us anything about the sizes of the households moving into or out of Weston. Nor do they tell us anything else that would support a reasonable inference about migration into or out of Weston. So (E) has no bearing on the conclusion that the number of people living in Weston has decreased.

A survey of address changes filed with post offices and driver’s

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A survey of address changes filed with post offices and driver’s

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

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