A clothing retailer bought 2 shipments of equal numbers of dresses at

Question

A clothing retailer bought 2 shipments of equal numbers of dresses at the same price. When the first shipment was sold in its entirety at $70 per dress, it generated $1,600 in profits. When the retailer sold the second shipment in its entirety at $90 per dress, it generated $2,400 in profits. What was the total number of dresses in both shipments?

(A) 40 
(B) 50 
(C) 60 
(D) 80 
(E) 100

kablayi · Answer

Lets say there were x number of dresses in each shipment. And cost of the each dress is y. Then we can set up following equation:

70x - xy = 1600
90x -xy = 2400

20x = 800

x= 40

Therefore there are 80 dresses in both shipments

Munch · Answer

Two shipments equal number of dress, Let dress be x , y be the price of each dress 
1. Given 70x = 1600 + xy
2. Given 90x =2400+xy

(note 1600 and 2400 is the profit) Equate with xy 
90x-2400=70x-1600
20x =800
x= 40

The question is total number of shpments, so it is 40+40 = 80

Ans : D

Mo2men · Answer

Dresses in Shipment 1 = S1 = n
Dresses in Shipment 2 = S2 = n

Cost per shipment = C

Profit = Revnune - Cost

For S1: 1600 = 70n - C

For S2: 2400 = 90n - C

Note: The cost of both shipments is the same as both shipment are identical of terms of number and cost per dress.

Subtract equations

800 = 20n...........n =40 dress per shipment

Then Toyla shipment = 80 dresses

Answer: D

KarishmaB · Answer

Since the number of dresses and cost price is the same in both, 
Simply note that an extra $20 charge ($90 sale price instead of $70 sale price) led to an extra profit of $800 (= 2400 - 1600).
So there must have been 800/20 = 40 dresses in one lot.
This means a total of 80 dresses.

Answer (D)

puneetj88 · Answer

Let No. of dresses be n and original cost per dress be x

Then 70n=x+1600
 90n=x+2400

Solving gives n=40

Thus total dresses is 2n=80

Ans:D

Kinshook · Answer

Given:  A clothing retailer bought 2 shipments of equal numbers of dresses at the same price. When the first shipment was sold in its entirety at $70 per dress, it generated $1,600 in profits. When the retailer sold the second shipment in its entirety at $90 per dress, it generated $2,400 in profits.

Asked:  What was the total number of dresses in both shipments?

Let the total number of dresses be 2x.

First shipment:-
SP = $70x
Profits= $1600
CP = $70x - $1600

Second shipment: - 
SP = $90x
Profits = $2400
CP = $90x - $2400

Since both shipments were purchased at same price

CP = $70x - $1600 = $90x - $2400
$20x = $800
x = 40
2x = 80

IMO D

bumpbot · Answer

Automated notice from GMAT Club BumpBot: 

A member just gave Kudos to this thread, showing it’s still useful. I’ve bumped it to the top so more people can benefit. Feel free to add your own questions or solutions.

 This post was generated automatically.

A clothing retailer bought 2 shipments of equal numbers of dresses at

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

GMAT Problem Solving (PS) Questions

A clothing retailer bought 2 shipments of equal numbers of dresses at

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