October 2010 LSAT Section 1 Question 7
Which one of the following most accurately expresses the main point of the passage?

1 Reply

on October 10, 2019
Hello @pajberman,To answer your first question, Mehran only introduced the 20 LH and 80 RH as an example. Bringing the population to 100 total just makes it easier to work with percentages. It could have been 70-30 or 60-40, but he just chose to work with 80-20.
To answer your second question, the myth does not say that LH people have more accidents. It says they are more prone to cause accidents. These are not the same.
Let's keep in mind an important distinction. "Prone to cause accidents" only means that left-handed people are more likely to cause accidents. We cannot make a claim about total number of accidents. This is why the support given by the author is not good enough to dispel the myth. RH people can still cause more total accidents, while LH people are still more accident-prone. It all depends on the population size. This is where Mehran brings in the 20-80 example to demonstrate the flaw in the argument.
Maybe it will be more clear if I write it out. Remember that accident-proneness is determined by the rate of accidents, not by the total number.
LH Population: 20
Accident rate: 75%
Total Accidents: 15
RH Population: 80
Accident Rate: 25%
Total Accidents: 20
This eliminates the only support that the author provides. We have created a scenario in which RH caused more accidents, but LH were more accident-prone. The myth still remains.