If the airspace around centrally located airports were restricted to

+1 C

There are tow types of private planes: those with radar and those without it.
Those with radar are allowed to fly in the restricted area.
Those without radar cannot fly in the restricted area, and they are a lot.

+1C
To be noted question is "Assumptions of the conclusion drawn in the first sentence"


(A)Outlying airfields would be as convenient as centrally located airports for most pilots of private planes. -- not concerned about airfields

(B)Most outlying airfields are not equipped to handle commercial-airline traffic. -- not concerned about airfields

(C)Most private planes that use centrally located airports are not equipped with radar. -- Correct --- There is a restriction for private planes without radar, coz of this most of planes are outside airport (means most of them are without radar)

(D)Commercial airlines are at greater risk of becoming involved in midair collisions than are private planes. -- We are concerned about private planes specifically not general commercial airlines

(E)A reduction in the risk of midair collision would eventually lead to increase in commercial airline traffic. -- This is assumption of final conclusion

Conclusion in first sentence- most of the private-plane traffic would be forced to use outlying airfields
Pre-thinking - Most of private planes that use centrally located airport are not equipped with radar .

Answer C

If the airspace around centrally located airports were restricted to commercial airliners and only those private planes equipped with radar, most of the private-plane traffic would be forced to use outlying airfields.Such a reduction in the amount of private-plane traffic would reduce the risk of midair collision around the centrally located airports

Since the objective is to reduce the traffic thereby reducing risk of midair collision at centrally located airports, retaining private places with radar to centrally located airports and shifting the rest of the private-plane traffic to outlying airfields would only result in reduced traffic at centrally located airports -> if the private planes with radar are much less than private planes without radar, which is what has to be the clear assumption of the one who is making this statement. Else there is no point in retaining the private planes with radar to centrally located airports if their quantity is not substantially less.
Therefore C is CORRECT

If the airspace around centrally located airports were restricted to commercial airliners and only those private planes equipped with radar, most of the private-plane traffic would be forced to use outlying airfields.Such a reduction in the amount of private-plane traffic would reduce the risk of midair collision around the centrally located airports

Conclusion: Reduction in mid air conclusion
Premise: Airspace = restricted = only comm/private planes with radars.
Private planes = Reduced = reduction in collision
Assumption: Private planes are without radars.

The conclusion drawn in the first sentence depends on which of the following assumptions?

(A) Outlying airfields would be as convenient as centrally located airports for most pilots of private planes．
They are changing the routes not because of convenience but because of safety ( Radar )

(B) Most outlying airfields are not equipped to handle commercial airline traffic．
Well we are talking about an assumption of collision of flights and not the handling.

(C) Most private planes that use centrally located airports are not equipped with radar．
My background information

(D) Commercial airliners are at greater risk of becoming involved in midair collisions than are private planes．
Who is at a greater risk is not ou concern. Why the reduction happened is our concern.

(E) A reduction in the risk of midair collision would eventually lead to increases in commercial airline traffic．
Out of scope.

If the airspace around centrally located airports were restricted to commercial airliners and only those private planes equipped with radar, most of the private-plane traffic would be forced to use outlying airfields. Such a reduction in the amount of private-plane traffic would reduce the risk of midair collision around the centrally located airports

The conclusion drawn in the first sentence depends on which of the following assumptions?

conclusion drawn in the first sentence - most of the private-plane traffic would be forced to use outlying airfields

(A) Outlying airfields would be as convenient as centrally located airports for most pilots of private planes．
As per the above argument, most of the private-plane traffic would be forced (they have no choice or any other possible option) to use outlying airfields due to the restriction of the airspace around centrally located airports to only those private planes, which are equipped with radar. It does not talk about whether the outlying airfield would be as convenient as centrally located airports or not. Thus, this option is incorrect.
Convenience related to airfield usage is not talked about in the argument, so is irrelevant as we cannot comment on that.
The conclusion need not assume that outlying airfields are convenient for private planes, since the restrictions would give planes (that are not radar equipped) any/no choice.


(B) Most outlying airfields are not equipped to handle commercial-airline traffic．
Negate - Most outlying airfields are equipped to handle commercial-airline traffic．
As per the premise, the centrally located airports should be restricted to commercial airliners and private planes equipped with radar.
So, it does not matter even if the outlying airfields are equipped to handle commercial-airliners because commercial airliners will still be using the centrally located airports. The negation does not break the argument and the argument stands as it is. Therefore, this option statement is not an assumption.

(C) Most private planes that use centrally located airports are not equipped with radar．
Negate - Most private planes that use centrally located airports are equipped with radar．
This negation will break the conclusion of the first statement, if most of the private planes are equipped with radar, then most of them will be using the central located airport and not the outlying airfields. (most of the private-plane traffic would be forced to use outlying airfields).
Therefore, this is the assumption.

(D) Commercial airliners are at greater risk of becoming involved in midair collisions than are private planes．
This cannot be the assumption for the first statement. Also, this option statement goes against the main conclusion of this argument.

(E) A reduction in the risk of midair collision would eventually lead to increases in commercial airline traffic
Firstly, this is talking about the future, which may or may not be true to happen.
Secondly, this option statement does not provide a missing gap between the premise and the conclusion in the first statement.


Also, options B, D and E, which deal with commercial planes and with risk of midair collision, need not be assumed. As the conclusion of the first statement deals with the volume of the private-planes traffic and not with the mid air collision or the commercial planes.

VeritasKarishma:

Am I correct when I say that this question has two conclusion statements - 1st and 2nd sentence. However, 2nd sentence is the conclusion of the argument and 1st sentence acts as a premise for the conclusion of the argument (i.e. 2nd conclusion statement)?

Thanks,

The structure of the argument is:

If A happens, B will happen.
Conclusion of the argument: B will reduce the risk of C.

The conclusion drawn in the first sentence is "B will happen." Based on this (often called the intermediate conclusion), the conclusion of the argument is drawn in the second sentence.

KarishmaB Ma'am,

Is my negation for answer choice C correct?

This is the correct answer choice because if most private airplanes are not equipped to use radar, they would automatically be diverted to the outlying air fields. This strengthens our conclusion.
When we negate this option statement we get "Less than or upto 50% of the private planes are not equipped with radar". So if this is the case then there are fewer planes that don't use radar. Hence, fewer would be forced to use outlying air fields. This weakens the conclusion. Hence, this is the correct answer choice.

Yes, this is correct.

Posted from my mobile device

Hi, the 1st statement in the question says that if the airspace around centrally located airports is ''restricted" to commercial flights and private planes only with radar, most of the private plane traffic would be forced to use outlying airfields. Now, isn't this a fact?

If we take this as a fact, we KNOW for sure that most of the private planes will not use the airspace around centrally located airports.

Now, the 2nd statement says - ''such a reduction in the amount of private-plane traffic would reduce the risk of midair collision around the centrally located airports''. So, given the fact in the 1st statement, the reduction of private planes in the airspace around the centrally located airports is bound to happen and that will reduce "risk of midair collision". Therefore, that reduction will reduce risk of midair collision is our main conclusion.

Then, how can option C be the right choice - Most private planes that use centrally located airports are not equipped with radar?
We already know, for a fact, that since the private plane reduction in the airspace around the centrally located airports is bound to happen (as mentioned in the 1st statement), they must not be equipped with radar (inferring from the fact).

Please help. GMATNinja KarishmaB egmat

Focus on the question stem:
The conclusion drawn in the first sentence depends on which of the following assumptions?

It is talking about the CONCLUSION drawn in the first sentence.

First sentence:
If the airspace around centrally located airports were restricted to commercial airliners and only those private planes equipped with radar, most of the private-plane traffic would be forced to use outlying airfields.

Highlighted is the conclusion.

If A happens, B will happen.
Conclusion is that B will happen.

How can we say that most private places would be forced to use outlying airfields? Because they must not have radar.

Answer (C)

The second sentence of the argument is useless information because the question stem has only focused on the first sentence.

Option (A): Outlying airfields would be as convenient as centrally located airports for most pilots of private planes.
Negation: Outlying airfields would not be as convenient as centrally located airports for most pilots of private planes.
If outlying airfields are not convenient for most pilots, then equipping planes with radar may not actually force them to switch to those airfields. This breaks the reasoning of the argument. Hence, this assumption is necessary for the conclusion to hold.
Option (B): Most outlying airfields are not equipped to handle commercial-airline traffic.
Negation: Most outlying airfields are equipped to handle commercial-airline traffic.
This doesn't really affect the reasoning about private-plane traffic being forced to use outlying airfields, so it doesn't break the argument.
Option (C): Most private planes that use centrally located airports are not equipped with radar.
Negation: Most private planes that use centrally located airports are equipped with radar.
If most private planes are already equipped with radar, then equipping more planes wouldn't force them to use outlying airfields, but the conclusion focuses on the impact of future radar-equipped planes, so this negation doesn't break the argument.
Option (D): Commercial airliners are at greater risk of becoming involved in midair collisions than are private planes.
Negation: Commercial airliners are not at greater risk of midair collisions than private planes.
This is irrelevant to the argument because the focus is on reducing private-plane traffic and collision risks, not comparing risks between different types of planes.
Option (E): A reduction in the risk of midair collision would eventually lead to increases in commercial airline traffic.
Negation: A reduction in the risk of midair collision would not lead to increases in commercial airline traffic.
Whether commercial airline traffic increases or not does not impact the argument about forcing private planes to use outlying airfields.
Conclusion:
The correct answer is (A) because negating it breaks the argument, making it essential to the conclusion.