# pt 46 june 05, sect 3 lr q#22

#### big east boy

##### pt 46 june 05, sect 3 lr q#22
« on: September 15, 2008, 10:57:23 AM »
The credited answer is A.  What I don't understand is how more people under 18 living in the region helps the argument that there is an increasing number of people over 65 living in the region.  I put D as my choice.  My reasoning for this is that since the arg states more people over 65, and gets this from percentage evidence (avg.age increased from 52-57), then for the conclusion to be valid than there would have to be more people.  Otherwise a case could arise where there was a higher percentage of over65 but a lower number.  Any help is appreciated.

#### potato-potato

##### Re: pt 46 june 05, sect 3 lr q#22
« Reply #1 on: September 16, 2008, 07:03:49 AM »
Premise: average age in the region has increased to 57
Conclusion: in the last 10 years, people 65+ have increased dramatically in the region

(D) cannot be the correct answer because we don't know the ages of those who moved in/out of the region.  It could be that a bunch of 57 year old people moved in and everyone else moved out, and therefore the conclusion would not hold.

(A) states that a bunch of people under 18 have moved into the region.  Therefore, in order for the average age to rise even though the number of significantly younger people increase, it must be the case that significantly older people, 65+ have also increased in order to pull the average up.

#### vandyprincess

##### Re: pt 46 june 05, sect 3 lr q#22
« Reply #2 on: September 19, 2008, 02:15:52 AM »
unless my math is wrong... (D) can still be argued to be the right answer because if a bunch of people move into town, regardless of their age, there has to be an increase of 65+ for the average to increase anyway. say there was 52 seniors/100 townspeople last year (52%) and this year there's 114 seniors/200 townspeople. As the number of townspeople increase, the number of seniors must increase to justify the 57% or vice versa.

same logic as (A).