GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 20 Jul 2018, 15:34

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# John bought a total of 12 Mangoes and Oranges. Each Mango co

Author Message
TAGS:

### Hide Tags

Director
Joined: 29 Nov 2012
Posts: 818
John bought a total of 12 Mangoes and Oranges. Each Mango co  [#permalink]

### Show Tags

31 Jul 2013, 08:04
7
00:00

Difficulty:

55% (hard)

Question Stats:

73% (02:41) correct 27% (02:46) wrong based on 193 sessions

### HideShow timer Statistics

John bought a total of 12 Mangoes and Oranges. Each Mango costs 80 cents and each orange costs 60 cents. If the average price of the 12 mangoes and oranges that John originally purchased was 65 cents, then how many oranges needs to return to raise the average price of his purchase to 72 cents?

a) 4
b) 5
c) 6
d) 7
e) 8

_________________

Click +1 Kudos if my post helped...

Amazing Free video explanation for all Quant questions from OG 13 and much more http://www.gmatquantum.com/og13th/

GMAT Prep software What if scenarios http://gmatclub.com/forum/gmat-prep-software-analysis-and-what-if-scenarios-146146.html

VP
Status: Far, far away!
Joined: 02 Sep 2012
Posts: 1098
Location: Italy
Concentration: Finance, Entrepreneurship
GPA: 3.8
Re: John bought a total of 12 Mangoes and Oranges. Each Mango co  [#permalink]

### Show Tags

31 Jul 2013, 08:09
1
2
Using alligation (refer to my Mixture post in my signature) we get that $$\frac{M}{O}=\frac{1}{3}$$, so we have 3 Mangoes and 9 Oranges.

The number x of Oranges he has to return is:

$$\frac{3*0.8+(9-x)*0.6}{12-x}=0.72$$, solve for x and obtain $$x=7$$.

Hope it's clear, for the method I've used refer here tips-and-tricks-mixtures-151906.html
_________________

It is beyond a doubt that all our knowledge that begins with experience.

Kant , Critique of Pure Reason

Tips and tricks: Inequalities , Mixture | Review: MGMAT workshop
Strategy: SmartGMAT v1.0 | Questions: Verbal challenge SC I-II- CR New SC set out !! , My Quant

Rules for Posting in the Verbal Forum - Rules for Posting in the Quant Forum[/size][/color][/b]

Intern
Joined: 17 May 2013
Posts: 45
GMAT Date: 10-23-2013
Re: John bought a total of 12 Mangoes and Oranges. Each Mango co  [#permalink]

### Show Tags

31 Jul 2013, 09:55
Let number of mangoes be x, number of oranges be 12-x

0.80x +(12-x)0.60/12 = 0.65
solving for x, we get x = 3 --> Mangoes 3, Oranges 9

Now, number of oranges to be returned be y

0.80*3 + (9-y)*0.60/12-y = 0.72

solving for y, y = 7
Ans: D
Senior Manager
Joined: 23 Oct 2010
Posts: 364
Location: Azerbaijan
Concentration: Finance
Schools: HEC '15 (A)
GMAT 1: 690 Q47 V38
Re: John bought a total of 12 Mangoes and Oranges. Each Mango co  [#permalink]

### Show Tags

24 Sep 2013, 10:16
1
M 80 cents O=60cents Average= 65 then number of M/number of O=(65-60)/(80-65)=1/3

Since there are 12 fruits in total then we have 1x+3x=12 > x=3 M=1*3=3 ; O=3*3=9
**
M 80 cents O=60cents Average= 72 then number of M/number of O=(72-60)/(80-72)=3/2

note that the number of M hasnt changed, but the number of O has changed from 9 to 2
so, we need to remove 9-2=7 yummy oranges
_________________

Happy are those who dream dreams and are ready to pay the price to make them come true

I am still on all gmat forums. msg me if you want to ask me smth

Manager
Joined: 04 Sep 2012
Posts: 99
Location: Philippines
Concentration: Marketing, Entrepreneurship
Schools: Ross (Michigan) - Class of 2017
GMAT 1: 620 Q48 V27
GMAT 2: 660 Q47 V34
GMAT 3: 700 Q47 V38
GPA: 3.25
WE: Sales (Manufacturing)
John bought a total of 12 Mangoes and Oranges. Each Mango co  [#permalink]

### Show Tags

02 Jul 2014, 17:32
fozzzy wrote:
John bought a total of 12 Mangoes and Oranges. Each Mango costs 80 cents and each orange costs 60 cents. If the average price of the 12 mangoes and oranges that John originally purchased was 65 cents, then how many oranges needs to return to raise the average price of his purchase to 72 cents?

a) 4
b) 5
c) 6
d) 7
e) 8

There is no need to even calculate this. A 50-50 split between mangoes and oranges give a price of 70 cents. Since 72 cents is a little bit above the arithmetic mean, we should also pick an answer a little bit above the arithmetic mean.

Target Test Prep Representative
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 2973
Location: United States (CA)
Re: John bought a total of 12 Mangoes and Oranges. Each Mango co  [#permalink]

### Show Tags

20 Jun 2017, 07:30
fozzzy wrote:
John bought a total of 12 Mangoes and Oranges. Each Mango costs 80 cents and each orange costs 60 cents. If the average price of the 12 mangoes and oranges that John originally purchased was 65 cents, then how many oranges needs to return to raise the average price of his purchase to 72 cents?

a) 4
b) 5
c) 6
d) 7
e) 8

We can let the number of mangos = m and number of oranges = r. We can create two equations:

m + r = 12

m = 12 - r

and

65 = (80m + 60r)/12

780 = 80m + 60r

78 = 8m + 6r

39 = 4m + 3r

Since m = (12 - r), we have:

39 = 4(12 - r) + 3r

39 = 48 - 4r + 3r

9 = r

Since r = 9, m = 3.

Let’s let x = the number of oranges to return. We can create the following average equation:

72 = [80*3 + 60*(9-x)]/(12 - x)

72(12 - x) = 240 + 540 - 60x

864 - 72x = 780 - 60x

84 = 12x

7 = x

_________________

Scott Woodbury-Stewart
Founder and CEO

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

VP
Joined: 07 Dec 2014
Posts: 1036
Re: John bought a total of 12 Mangoes and Oranges. Each Mango co  [#permalink]

### Show Tags

29 Oct 2017, 12:02
fozzzy wrote:
John bought a total of 12 Mangoes and Oranges. Each Mango costs 80 cents and each orange costs 60 cents. If the average price of the 12 mangoes and oranges that John originally purchased was 65 cents, then how many oranges needs to return to raise the average price of his purchase to 72 cents?

a) 4
b) 5
c) 6
d) 7
e) 8

let x=number of oranges needed to return
72¢=(12*65¢-x*60¢)/(12-x)
x=7 oranges
D
Re: John bought a total of 12 Mangoes and Oranges. Each Mango co &nbs [#permalink] 29 Oct 2017, 12:02
Display posts from previous: Sort by

# Events & Promotions

 Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.