Unless the residents of Glen Hills band together, the proposal to rezo

Ans (B)

IMO B If developers build apartment houses in Glen Hills, there will be substantial tax increases for the residents of Glen Hills


Unless the residents of Glen Hills band together, the proposal to rezone that city will be approved. If it is the city will be able to build the water and sewer systems that developers need in order to construct apartment houses there. These buildings would attract new residents. and the increased population would probably result in overcrowded schools and would certainly result in roads so congested that new roads would be built. Neither new roads nor additional schools could be built without substantial tax increases for the residents of Glen Hills, Ultimately this growth might even destroy the rural atmosphere that makes Glen Hills so attractive.

Which one of the following can be properly concluded from the passage?

(A) If the citizens of Glen Hills band together. developers will not build apartment houses

(B) If developers build apartment houses in Glen Hills, there will be substantial tax increases for the residents of Glen Hills

(C) If the rezoning proposal does not pass the rural atmosphere in Glen Hills will not be lost

(D) If developers do not build apartment houses in Glen Hills, the taxes of the residents of Glen Hills will not increase substantially

(E) If developers do not build apartment houses in Glen Hills. the schools of Glen Hills will not be overcrowded and roads will not be congested

band-->rezone-->build the water and sewer systems-->construct apartment houses -->attract new residents-->increase population -->overcrowded schools-->road will be congested and new one builds -->substantial tax increases for the residents of Glen Hills

(A) If the citizens of Glen Hills band together. developers will not build apartment houses........INCORRECT....the converse is correct

(B) If developers build apartment houses in Glen Hills, there will be substantial tax increases for the residents of Glen Hills....CORRECT

(C) If the rezoning proposal does not pass the rural atmosphere in Glen Hills will not be lost.....NOT REALLY....e cannot say that

(D) If developers do not build apartment houses in Glen Hills, the taxes of the residents of Glen Hills will not increase substantially.....NOT REALLY....e cannot say that


(E) If developers do not build apartment houses in Glen Hills. the schools of Glen Hills will not be overcrowded and roads will not be congested.....NOT REALLY....e cannot say that



OA: B

Hi eakabuah
I have gone through your explanation. I might be asking a silly question but by false-negative is it meant that only the immediate chain element is concluded or vice-a-versa.

Can you help.

Not a silly question at all lnm87
For any given conditional relationship, lets say B is the necessary condition and A is the sufficient condition.
so the diagram for the relationship between A and B is:
A---->B.
we can form three other logical relation from the above information. Two are wrong and the other is right. The right logical deduction from the diagram above is called contrapositive. It simply means, reverse the relationship and negate the conditions.
The contrapositive for A---->B is not B----->not A. A---->B means that if A occurs, then B must have occurred. So if B has not occurred, then we can say that A has not occurred either; this is the contrapositive.
False negative:
not A---->not B. This is not a valid logical deduction. The fact that when A occurs then B must have occurred does not mean that when A does not occur then B did not occur either.
False reversal:
B----->A. This is also not a valid logical deduction from A---->B. The fact that the occurrence of A means that B must have occurred does not mean that when B occurred then A must also have occurred.

Let me simplify the concept of the logic chain by using letters. If we have the following conditional statements,
A---->B
B---->C
C---->D
D---->E
E---->F
we can form the chain below from the conditional statement above.
A---->B----->C----->D----->E----->F
Along the chain, I can deduce that
A--->B, A---->C, A----->D, A---->E, and A----->F
B--->C, B---->D, B---->E, and B----->F
C--->D, C---->E, and C----->F.
D--->E and D---->F.
All of the above inferences are valid since they follow along the logic chain.
The moment you reverse order without negating the conditional terms, then you have a false reversals. For example E----->B, F---->A, D---->C are all false reversals of the valid conditional relationship established in the chain.
Likewise, falsely negation occurs when any of the following inferences are made from the chain: not A---->not B, not A--->not C, not A---->not D, etc.

When you now take these into consideration, you will realize that all the options for the question falsely negated the relationships in the logic chain except option B, which has a valid inference.

I hope I have somehow cleared your doubts to some extent. You can refer to powerscore CR bible for more detailed explanation on conditional reasoning.

Thanks for such a detailed explanation. I had a similar understanding after your earlier post but this one cleared everything.
Any such OG questions that you have come across ?

lnm87
Unfortunately, I have not come across any OG question like this one.

Exactly.
I even have not seen one. I will still scavenge.

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