According to a recent census, West Egg had more mansions per ca-pita

Shouldn't 'C' also be the right answer here,

Per Capita for west:
8/10 = 0.8

Per Capita for East:
5/9 = 0.55

0.8 > 0.55

I picked C and I'm still not sure why this isn't the right answer.

My Approach to solve this one is .......

1) West egg more mentions per capita than East engg (number of mansions / total population )
2) East engg has slightly fewer residents (assume equal) to West engg .

Now from these points you can infer that West has more mansions than East has .

Also this point says , demolition has equal impact on both east and west mansions ....this tells number of mensions reduced in east is equal to that of west .
So we can say that west still has more mansions than east has .

Why is E wrong?

In must be true question rephrasing premise is also a correct answer

picked E. I can see how B can possibly be correct but E is not incorrect.

Hi chetan2u / daagh,

I am stuck between B and C.
OA is B.
Can you please assist why is C incorrect.

Hi,
E is incorrect because we are not told anything about the change in population

if the population has increased in west and decreased in east, YES..
But if the population has decreased in west and increased in east, NO..

We cannot assume that the relative value of last year are true for this year unless specified

Hey Guys
Look at these two sentences:
West Egg had more mansions per ca-pita last year than East Egg, while East Egg had slightly fewer residents than West Egg.
Pay attention to "slightly" which means:
West Egg mansion per capita * residents > East Egg mansion percapita* residents
And both West Egg and East Egg will demolite same amount of mansions, so still, West Egg mansions are more than East Egg.

As per chetan2u 's logic,nothing can be assumed about the change in population, as it could have increased or decreased. This is the reason why E is incorrect and why C is uncertain.

C talks about mansion per capita = Total mansion/Total population. Since, this option is dependent on population and we are uncertain about fluctuation in population between the two points, C is uncertain.

However, going by the same logic, B is also uncertain. B talks about number of mansions, which product of mansions per capita & total population. Since the answer is dependent on total population and following the logic that you stated for C and E, their is a possibility that population of West Egg has declined extremely drastically and is now way less than East Egg. In that scenario, the number of mansions will be less in West Egg then East Egg.
If we are using the logic that we cannot assume population increase or decrease and ruling out option E and C, we should apply the same logic to A.

Hi sonaxi..
You are correct that the mansions are dependent on population and per capita..
So let's see what was the case before demolition..
W had more mansions per capita and more population too last year..
So ofcourse more mansions per capita and more population MEANS more mansions last year..

Now what has happened since last year..
Same number of mansions are demolished. So same number being taken out, the larger number will remain larger..
So We has more mansions than E..
B should be true and certain

Veritas Prep Official Explanation:

The question reveals that West Egg had more mansions per capita and East Egg had fewer people. But “since the census” all we know is that both West Egg and East Egg have 12 fewer dilapidated mansions. We can conclude only that the total number of mansions in both places has decreased equally, and therefore West Egg must still have more mansions than East Egg. We do not have any information about the residents after the census. It’s possible East Egg’s population has increased dramatically, or that West Egg’s has decreased. We therefore cannot make any conclusions “per capita.”

OFFICIAL EXPLANATION

The correct answer is (B).

The question reveals that West Egg had more mansions per capita and East Egg had fewer people. But “since the census” all we know is that both West Egg and East Egg have 12 fewer dilapidated mansions. We can conclude only that the total number of mansions in both places has decreased equally, and therefore West Egg must still have more mansions than East Egg. We do not have any information about the residents after the census. It’s possible East Egg’s population has increased dramatically, or that West Egg’s has decreased. We therefore cannot make any conclusions “per capita.”

Hi experts,
Even though I have read all the above comments I still can't understand why I should choose B over E. Could somebody shed some light on this problem?

West Egg had more mansions per capita last year than East Egg, while East Egg had slightly fewer residents than West Egg

Mansion at West Egg = A. Mansions at East egg = B.
Residents at West Egg = X. Residents at East egg = Y.

As per the statement: A/X > B/Y

and Y< X
Now smaller denominator on B/Y side means for A = B, the condition cannot be true. Hence, A > B

Since the census, West Egg and East Egg have each seen the demolition of a dozen dilapidated mansions within their respective borders, and no new mansions have begun construction
The trick is to understand the "a dozen" is literally 12 mansions, and it is not used figuratively to mean considerable number of mansions.
Another observation is a year has passed since the demolition. Hence, we do not know the change in population within the year.

Hence after demolition, the inequality remains A-12 > B-12
Option B: West Egg has more mansions than East Egg.
Exactly what the inequality A-12 > B-12 says

Option E: West Egg has more residents than East Egg
As mentioned before, we are not sure what the change has been in the population since the census

We have not been given any statement about the number of people after

I've seen a few confusing theories above and would like to give my view on why B and not C.

C. Let us assume that there is no change in population then as the number of houses demolished are same there will be a variance in percaptia number of houses for each city and we can't capture all the conditions correctly.

B. Since the demolition is same we can clearly conclude that western egg has more number of houses than eastern egg.

Lets understand this problem with Tim, Jim, their friends and chocolates.

Tim <-> West Egg
Jim <-> East Egg
Friends <-> Residents
Chocolates <-> Mansion

Tim-> 10 friends -> 40 chocolates -> 4 chocolates per friend
Jim-> 5 friends -> 15 chocolates -> 3 chocolate per friend

West Egg has fewer residents than East Egg <-> Jim has fewer friends than Jim
Mansions per capita are higher in West Egg <-> Jim's group has higher chocolates per friend

Dozen (12) of mansions are demolished in both West Egg and East Egg<-> 12 chocolates are eaten both in Tim's group and Jim's group

Only certainty:
Mansions left in West Egg are still higher than East Egg (Answer Choice B) <-> 28 chocolates with Tim's group and 3 chocolates in Jim's group

B is correct but why E is wrong .??

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