pink_08 wrote:Hi,

Can somebody please clarify this CR from OG with a numerical example. Since there is a thread, I am referring the link below.( My question is in the last posting )
https://www.beatthegmat.com/og-11-81-t38524.html


pink

A recent report determined that although only three percent of drivers on Maryland highways equipped their vehicles with radar detectors, thirty-three percent of all vehicles ticketed for exceeding the speed limit were equipped with them. Clearly, drivers who equip their vehicles with radar detectors are more likely to exceed the speed limit regularly than are drivers who do not.

The conclusion drawn above depends on which of the following assumptions?
(A) Drivers who equip their vehicles with radar detectors are less likely to be ticketed for exceeding the speed limit than are drivers who do not.
(B) Drivers who are ticketed for exceeding the speed limit are more likely to exceed the speed limit regularly than are drivers who are not ticketed.
(C) The number of vehicles that were ticketed for exceeding the speed limit was greater than the number of vehicles that were equipped with radar detectors.
(D) Many of the vehicles that were ticketed for exceeding the speed limit were ticketed more than once in the time period covered by the report.
(E) Drivers on Maryland highways exceeded the speed limit more often than did drivers on other state highways not covered in the report.

The assumption here can be seen as a link between the premises and the conclusion.
The premises say drivers...ticketed but the conclusion only says drivers equipped with radars so look for a choice that link both.
I think it´s B.

answer is B coz it is clearly mentioned in the passage that the only 3% of the drivers are equipped with RDs (radar detectors) but 33% of total drivers who are ticketed are equipped with the detectors. and hence the drivers who are equipped with RDs are more likely to exceed the limit..
Here clear assumption is the missing evidence from the stimuli that led us to the conclusion is statement B that inspite of less no. of equipped drivers no. of drivers equipped with the detectors exceed the limit coz the same drivers are exceeding the limits again and again who are already ticketed once..

HTH..

Dont you think that B actually qualifies as an assumption, whereas D is more of an external statement that brings in outside information and can be used to strengthen

Ok the problem is choosing b/w B and D.

Lets look at D.

Let us suppose that 9 vehicles got caught and out of those 3 were with radar.Since many (few or may be all) of the vehicles were ticked more than once therefore there is a possibility that the rest of the 6 w/o radar may be ticket more than the ones with radar hence may not be an assumption.

B. Since the vehicles that are ticketed once may do it again means all the drivers will do so and hence the % would remain the same.

Hope this suffices though I know its not a very clear distinction its quite subtle but thats all we need.

I think D is the right answer here.