During a sale, for each shirt that Mark purchased at the regular price

Question

During a sale, for each shirt that Mark purchased at the regular price, he also purchased a shirt at half the regular price. How many shirts did Mark purchase during the sale?

(1) The regular price of each of the shirts that Mark purchased during the sale was $21.50.
(2) The total of the prices for all the shirts that Mark purchased during the sale was $129.00.

prasannar · Answer

C for me

How many shirts did Mark purchase during the sale?

We need the total amount/ unit price= #

Stmt-> (1) The regular price of each of the shirts that Mark purchased during the sale was $21.50. Insuff

(2) The total of the prices for all the shirts that Mark purchased during the sale was $129.00.
Stmt-2 insufficient since we have two unknowns

combining 1&2 we can solve the problem thus C

vd · Answer

I think C is the only straight forward answer here 
what is the OA for this one

sondenso · Answer

With your general reasoning and with my work already overload :-D

, I still not figure out the OA! Here is my reasoning: 1. x is number of shirts she buy with regular price 2. y is number of shirts she buy with 1/2 regular price. Question asks x+y=? So, from statement1: x*21.5 +y*21.5/2 =...? so not suff from the statement2: x*21.5 +y*21.5/2 = 129, so stil not suff Comebine state 1 and 2 still not help! so E, help me out what wrong with my reasoning! Thanks!

kevincan · Answer

Keep in mind that x=y

sondenso · Answer

Why do you think that x=y?

prasannar · Answer

assuming that Mark purchased a shirt for $X he also purchased a shirt for $X/2 if the regular price means different prices then it has to be E.

chengliu · Answer

Answer should be C

p = price of shirt
x = quantity of shirt purchased
we know that for each reg price shirt purchased, there was a purchase of one half priced shirt

px+ 1/2px = 129

px(1+1/2) = 129
px = 86

we know p=21.50

we can solve for x

JovanneMBA · Answer

I agree that C is the answer.

From (1) we know that the price of 1 shirt at full price is $21.50.

From the question stem, we know that with each purchase of 1 full price shirt, there is an additional purchase of a half-priced shirt at $10.75.

From (2) we know that the total amount spent on shirts was $129.00.

Set-up:

Note: x is the total number of shirts purchased at a given price point

21.5x +10.75x = 129
32.25x = 129
x = 4

So we know that 4 shirts were purchased at each of the two price points, resulting in the total purchase of 8 shirts.

jallenmorris · Answer

I came up with C for the answer too, but also see the point made by a previous post.

The question does not say the 1/2 price shirt is of the same value. If it was a typical sale where you buy 1 shirt at regular price, get one of equal or lesser value for 1/2 price, then you don't know for sure that every 1/2 price shirt was the same original price as the shirt bought at full price.

kevincan · Answer

Doesn't (1) say so?

jallenmorris · Answer

kevincan,

You're right, 1 does say that the regular price for each shirt purchased was $21.50. In order to figure out the number of shirts purchased, we need the amount each shirt sold for originally (provided), the ratio of regular price to on-sale shirts (provided) and the total amount (not provided).

We cannot approach #2 with the knowledge of #1 until we're trying to determine if both together work. #2 tells us the total amount, but nothing as to the regular price for each shirt.

When combining the information, then we get C for the reason(s) you mentioned.

fozzzy · Answer

What's the official answer for this question?

KarishmaB · Answer

The answer here is (C) and not (E).

(1) The regular price of each of the shirts that Mark purchased during the sale was $21.50.

Statement 1 clearly tells you that the regular price of every shirt that he purchased (whether he purchased it at regular price or half price) is $21.50. There is no reason to assume that the regular price of shirts he purchased at half price might be different. The statement tells you that regular price of every shirt he took with him is $21.50.

Shrey1 · Answer

Assuming the shirts purchased at regular price is X and shirts purchased for 50% discount is Y.

Statements 1 & 2 are clearly insufficient.

Solving both statements together gives us the -

X + Y/2 = 129/21.5 = 6

From this, the values we can get are X=3, Y=6 & X=4, Y=4 & X=2 & Y=8. So, there is not a definite value for the total number of shirts bought by Mark.

That's why I would go with E.

KarishmaB  am I missing something here?

KarishmaB · Answer

Shrey1

X must be equal to Y. We are given that for each shirt he bought at regular price, he bought one at half price. So if he bought X shirts are regular price, he bought the same X shirts at half price. It is a sale - buy one shirt at regular price, get another at half price. You cannot buy shirts just at half price without buying one at regular price. You are expected to understand this from context.

bumpbot · Answer

Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.

During a sale, for each shirt that Mark purchased at the regular price

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Data Sufficiency (DS) Questions

During a sale, for each shirt that Mark purchased at the regular price

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards