求助：feifei逻辑135-23

ran2010zx

On acertain day, nine scheduled flights on Swift Airlines were canceled.Ordinarily, a cancellation is due to mechanical problems with the airplanescheduled for a certain flight. However, since it is unlikely that Swift wouldhave the mechanical problems with more than one or two scheduled flights on asingle day, some of the nine cancellations were probably due to something else.
(A) More than one or two airplanes werescheduled for the nine canceled flights.
(B) Swift Airlines has fewer mechanicalproblems than do other airlines of the same size.
(C) Each of the canceled flights would havebeen longer than the average flight on Swift Airlines.
(D) Swift Airlines had never before canceledmore than one or two scheduled flights on a single day.
(E) All of the airplanesscheduled for the canceled flights are based at the same airport.答案是A，不过我表示根本没看懂解释，也不理解为啥是A

ran2010zx

This an old LSAT question. LZ, you forgot to paste the question for a necessary assumption. For necessary assumption, use negation method.

The stimulus says that "it is unlikely that Swift would have the mechanical problems with more than one or two scheduled flights on a single day," the cancellation is caused by something else.

If you negate A, you get ""NO more than one or two airplanes were sheduled for the nine canceled filights." If this is true, then it is likely the cancellation is caused by nothing but mechanical prolbems with the one or two airplanes for the 9 flights.  Thus the argument falls apart.

A is the correct answer.

-- by 会员 sdcar2010 (2011/2/20 1:12:03)

好像有点点懂了，看来取非是不二法门啊哈哈。谢谢啊

sdcar2010

This an old LSAT question. LZ, you forgot to paste the question for a necessary assumption. For necessary assumption, use negation method.

The stimulus says that "it is unlikely that Swift would have the mechanical problems with more than one or two scheduled flights on a single day," the cancellation is caused by something else.

If you negate A, you get ""NO more than one or two airplanes were sheduled for the nine canceled filights." If this is true, then it is likely the cancellation is caused by nothing but mechanical prolbems with the one or two airplanes for the 9 flights.  Thus the argument falls apart.

A is the correct answer.