IanStewart wrote:
As far as the GMAT is concerned, what you are saying is not true. From the tone of your post, I don't get the impression you're interested in a civil conversation, so I won't try to have one, but if you're interested in further explanation, perhaps you can find another GMAT expert who is willing to discuss this with you.
I'm only replying to affirm that what I wrote above is correct, at least as far as GMAT CR arguments are concerned, for the benefit of other test takers who might read this thread.
@IanStewat sir,
Sir I just wanted to clear some air here. I feel that you and LogicGuru are both correct. For example for the question below:
Major airlines will purchase many of the new aircrafts capable of carrying more than 500 passengers on transcontinental and transoceanic flights. These airlines currently rely on "hub and spoke" systems of routing, in which large planes, which can seat 400 people and are capable of transoceanic flight, fly into hubs that have runways sufficiently long to handle them. From there, passengers are dispatched to local airports on connecting flights on small planes. With takeoff and landing time slots almost completely booked at most hubs, and little new runway construction expected, airlines will want to expand the volume of passengers they can fly in a given time slot.
The argument above would be most weakened if which of the following were true?
A. The new 500 seat aircraft cost more per seat than existing aircraft
B. Air traffic control systems at most hub airports cannot handle any more flights per hour than they currently do
C. The new 500 seat aircraft require boarding times substantially longer than those of existing aircraft
D. Small passenger aircraft, capable of efficient transcontinental and transoceanic flight and able to land on short runways, have come into service
E. Transoceanic air flights are currently running at near maximum capacity
OA is D.
Here D is giving us some new information that can be used to weaken the argument. I feel that LogicGuru's explanation is correct in the sense that option A is incorrect because opposite of 'All' is ' Not All' which basically leads to some/many. Since even if some people lose interest, even then it is not weakening the argument.
Kindly provide some insight since you guys are the experts!