prachich1987 wrote:

sanju09 wrote:May I interrupt?

MRP = $Z

Discounted price = $Y

Nina paid = $0.9 Y = $X

$0.1 Y = $X/9 =?

[1] Y = 0.9 Z, we're still missing a relation in X and Z to answer X or Y uniquely. Insufficient

[2] When the new value of Y is Y + 20, X = Y + 20 - 14 = Y + 6; now this is ambiguous to me, how can 90 percent of Y be more than Y, specially when we're dealing in positive numbers only?
--- I have a difficulty in understanding this.We are nowhere told that 90% of Y is more than Y.
But the new equation will become
(Y+20)*0.9=Y+6
0.9Y+18=Y+6
0.1 Y = 12---- This is what we were asked to find out.
Hence statement 2 is sufficient.
Please advise if I am going wrong anywhere

I agree with you... since from the question X is 0.9Y.... therefore the new price paid will be 0.9(Y+20)

aleph777 wrote:Here's my take: E.

OA?

z = retail price
y = discount price
x = y - .1y (the additional 10% discount)

SOLVE FOR .1y.

1) y = .9z
Insuf because we have no info about dollar amounts.

2) y + 20 = x - 14
Insuf because we can't solve for any static dollar amounts. y could be 80 and x could be 114. etc.

Combined? We still have no info about the retail price, the discount price, or the deep discount price that Nina paid.

IMO, Answer: E.

statement 2 should be y+20 = x+14 because x is $14 less than this new value of y
so x+14 = new value of y !!!

Hello all, this is my first post.

I stumbled upon this forum after struggling to find an explanation as to why this question, which I found on majortests.com, has an answer of (E).

I wish to add something to the discussion, as the previous posts helped me to find my answer, but didn't explicitly address my concerns. Perhaps this detailed explanation can help others looking for the same answer as I did.

I also initially strongly felt that (B) was the correct answer (statement 2 allowing you to find the answer of 12), and even tested it by plugging my answer into the original scenario.

The question is indeed incredibly badly worded (and there's no need to be concerned with this too much since an official GMAT problem will never be this badly worded.) However, it would be great to understand why (B) is not the answer, and what would have been needed for (B) to be the answer.

(B) would only be correct if the statement had read: "then THE NEW X would have been $14 less than this new value of Y".

In other words -
Y goes up by 20, 10% of which is 2.
The difference between NEW Y and NEW X is 14, 2 of which can be attributed to the increase in Y.
Difference between ORIGINAL X and ORIGINAL Y is therefore 12.

However, the statement claims that ORIGINAL X is 14 less than NEW Y. Since NEW Y is 20 higher than ORIGINAL Y, ORIGINAL X must be larger than ORIGINAL Y, which is impossible.

The answer to this particular question is therefore (E) not because it can't be calculated, but because it is impossible. Had the question been worded better / numbers been chosen differently, it would indeed be calculable from statement 2.