parallel reasoning

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parallel reasoning

by armaan700+ » Wed Feb 03, 2010 10:08 pm
If, in a tennis tournament, a match reaches a fifth-set tiebreak, the lower-ranked player always loses the tiebreak (and, therefore, the match). If Rafael, the second-ranked player, wins a tournament by beating Roger, the top-ranked player, then the match must not have included a fifth-set tiebreak.

Which of the following arguments most closely mimics the reasoning used in the above argument?
a) If a woman with a family history of twins gets pregnant three times, she will have one set of twins. Jennifer, who falls
into this category, had two sets of twins, so she must not have gotten pregnant exactly three times.
b) If a salesman sells more product than anyone else in a calendar year, then he will earn an all-expenses-paid
vacation. Joe earned an all-expense-paid vacation, so he must have sold more product than anyone else for the
year.
c) A newspaper can charge a 50% premium for ads if its circulation surpasses 100,000; if the circulation does not pass
100,000, therefore, the newspaper can't charge any kind of premium for ads.
d) If a student is in the top 10% of her class, she will earn a college scholarship. Anna is not in the top 10% of her class,
so she will not earn a scholarship.
e) All of the players on a football team receive a cash bonus if the team wins the Super Bowl. If quarterback Tom Brady
earned a cash bonus last year, he must have been a member of the winning Super Bowl team.

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by thephoenix » Wed Feb 03, 2010 10:31 pm
its pretty time consuming
let brk the argument in terms of if x , then y sort of

Question:
A = fifth set tiebreak
B = low rank player lose

If rafael wins = not B
then no fifth set tiebreak = not A

If A then B, if not B then not A

a)
A = family history of twins get pregnant 3 times
B = one set of twins
Jennifer had two set of twins = not B
not have gotten pregnant three times = not A
If A then B, if not B then not A
this is the answer

b)
A = sells more product than anyone else
B = vacation
If A then B, if B then A
so out

c)
A = if circulation > 100k
B = charge 50% premium
If A then B, if not A then not B
also out

d)
A = top 10% in class
B = scholarship
If A then B, if not A then not B
out

e)
assumption is based on all the players receiving cash bonus and not just an individual
out

HTH