totally confused

[atulmangal]

A recent report determined that only five percent of all homeowners in Stockton have outfitted their homes with burglar alarms. However, of the Stockton homes that have been burglarized within the last five years, 25 percent were outfitted with such alarms during the burglaries. Clearly, Stockton homeowners who outfit their homes with burglar alarms are more likely to become victims of burglary than are those who do not.

The conclusion above depends on which of the following assumptions?


(A) The number of homes in Stockton that were burglarized within the last five years is greater than the number of homes equipped with burglar alarms.

(B) A significant number of the homes in Stockton that were burglarized within the last five years were burglarized more than once within this time period.

(C) Homes that have been burglarized within the last five years are more likely to be burglarized than are homes that have not been burglarized within the last five years.

(D) Homeowners who outfit their homes with burglar alarms are less likely to become victims of burglary than are homeowners who have not installed such alarms.

(E) Homeowners in Stockton who have outfitted their homes with burglar alarms are more likely to be victims of burglary than homeowners with burglar alarms living in other similar cities.

[sourabh33]

IMO C

This question is an exact replica of question no 78 of OG 12. I recommend you go through the explanation provided in the OG.

The key here is that the author makes a generalization from a past trend. So if the opposite of C is true than the generalization may not be applicable, and therefore C is the answer.

Example

Given 1. 1000 Homes___50 With Alarm___950 Not With Alarm --> Probability of Alarm Homes to be victimized --> 50/1000

Given 2. 200 Burglaries_50 with Alarm_150 not with Alarm --> Probability of Alarm Homes to be victimized --> 50/200

[champmag]

+1 for C.
The author is comparing two very different things and reaching to the conclusion.

1.) Now only 5% of all the homes have fitted alarms.
2.) Five years ago 25% of the homes that were burglarized had alarms.

conclusion: Homes that have burgler alarms are more likely to become victims. How is this possible?
This is possible only when the possibility is high that homes that are already burglarized will be burglarized again.

Tough one actually. The answer can be zeroed on by elimination.

[abhi0697]

I will go with B as it clearly states that homes which were burglarized within last five years were burglarized more than once which resulted in higher percentage of homes having burglars that have been burglarized. This leads to conclusion.

[lunarpower]

this problem is ... let's just say ... very closely modeled on OG12 #78 (= OG11 #81), so you should probably just ignore it and study OG12 #78 instead -- you'll learn at least as much and probably more, and you'll actually be using an official problem.

here's an old thread from the manhattan forum, from the days when we were allowed to post OG questions there:
https://www.manhattangmat.com/forums/og-cr-81-t444.html