In a department store, all wine glasses are sold at the same

Question

In a department store, all wine glasses are sold at the same price. During a summer sale, all merchandise is marked down by 30%. How many wine glasses can be bought for $150 during the sale?

(1) Before the sale, at most four wine glasses could be bought for $100.
(2) During the sale, 21 glasses cost less than $300 but more than $290.

ak_idc · Answer

I think B is the answer. Atmost 10 glasses could be bought.

paddyboy · Answer

Yep B it is.

1 - If before the sale, max of 4 glasses could be bought for $100
then 20 < rate before discount <= 25

Now a 30% discount means the customer can buy for $150 what was earlier available for around $214. Since rate was $20 to $25, the customer can buy 8 to 10 glasses. Hence insufficient.

2 - During the sale 21 glasses cost less than 300 but more than 290.
=> rate is between around $13.8 to $14.3
=> for $150, the customer can buy 10 glasses only.

(unless he pays for a broken glass LOL! :lol:

)

And with that, I've solved my first kevincan (but paddy cannot) problem

) And with that, I've solved my first kevincan (but paddy cannot) problem

gauravgoyal_g · Answer

I think it should be D

With statement 1:
If x is the price of one glass
Originally, 4x <= 100, Hence x <= 25
After 20% discount
x<= 35/2
Hence, 8x <= 140 and 9x <= 157.5
Hence atmost 8 glasses can be bought

With statement 2:
If x is the price of one glass
290 < 21x < 300
Therefore 290/21 < x < 300/21
Multiplying inequality by 21/2
145 < 21x/2 < 150
Therefore at most 10 glasses can be bought

So either choice gives an answer...

Though I have a question here. I saw on some GMAT book that the two statements on GMAT would always agree, in other words they would always give the same value for x after solving. Is that not true?

Mikhail Bondarenko · Answer

Cicerone and gauravgoyal_g,

Statement 1 is insuff 'cause:

$100 buy you at most 4 glasses before the sale, meaning $70 buy up to 4 during the sale. 70/5 < x < 70/4 and x is anywhere between 14 and 17.5.

consider three x from this interval:

If x is 14.1, $150 wil buy you 10
If x is 17.4 $ 150 will buy you 8 
If x is 15.1, #150 will buy you 9

the band between 14.1*10 and 17.5*10 is too wide to give you one answer.

In B, As Clint Eastwood wrote, the band is very narrow 290/21 < x < 300 < 21, and not enough to fit a "new" $14 glass even if multiplied by 10.

Yurik79 · Answer

Tricky one) first choice D :oops:

but agree with B

Priyah · Answer

Hi,

I think D is the answer, though I get to buy 9 glasses with Statement 1 and 10 with Statement 2!

Statement 2 is suff because it gives us both the min and max values of the price of 1 glass.

Statement 1 does so too, though in a subtle way. It says we can pick up 4 glasses for $100, so it says that pre-sale price of one glass is less than or equal to 25, but def greater than 20 (if it were 20, we would be able to pick up 5 glasses at most with $100).

kidderek · Answer

A is insufficient. The price can range from $20.01 to $25. At a 30% discount, the prices are $14.01 to $17.50. With $150, you can buy up to 10 priced at $14.01, but you cannot when priced at $17.50. A is clearly insufficient.

Through all of my gmat prep, I've never encountered a correct D answer that had two different answers for A and B. That is almost a sure-fire way of knowing that you did something wrong. 

Has anyone come across a correct D answer that had two different answers for A and B?

haas_mba07 · Answer

Answer: B
If p = price before Sale...

S1: p < 25 Not sufficient..

S2: 
290 < 21 x 0.7p < 300

2900 < 21 x 7p < 3000

2900 < 147p < 3000

29 < 1.47p < 30
 
Approx. 29 < 1.5p < 30

or 29 < 3/2p < 30

or 58/3 < p < 60/3

or 19.3 < p < 20

Sufficient due to small range... !! (Please not on the GMAT...)

Answer: B

Priyah · Answer

Thank you both!
I guess it is these lil tips that seperate a great score from a good one!

In a department store, all wine glasses are sold at the same

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