Find all School-related info fast with the new School-Specific MBA Forum

It is currently 24 Sep 2016, 22:29
GMAT Club Tests

Close

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
Your Progress

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

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

A farmer spent $35 on feed for chickens and goats. He spent

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Intern
Intern
avatar
Joined: 05 Apr 2012
Posts: 12
Followers: 0

Kudos [?]: 4 [0], given: 3

A farmer spent $35 on feed for chickens and goats. He spent [#permalink]

Show Tags

New post 21 Apr 2012, 10:03
3
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  25% (medium)

Question Stats:

81% (02:51) correct 19% (02:45) wrong based on 116 sessions

HideShow timer Statistics

A farmer spent $35 on feed for chickens and goats. He spent 40% money on chicken feed, which he bought at a 20% discount off the full price, and spent the rest on goat feed, which he bought at full price. If the farmer had paid full price for both the chicken feed and the goat feed, what amount would he have spent on the chicken feed and goat feed combined?

A. $37.80
B. $38.50
C. $39.20
D. $39.50
E. $40.60

I set up the equation as follows: (C for chicken feed and G for goat feed)
0.8x0.4xC + 0.6G =35---a
0.4C+0.6G=35+?----b
equation b is 8% greater than a so I multiplied 35 by 8%, getting $2.8. Thus, I selected 37.8 but the answer is 38.50.
Q: could anyone please kindly point out what went wrong here?

The OA explanation is as follows but I can't understand the part in bold
0.4($35)=F (full price of chicken feed)
$14=0.8F

$17.5=F
Total paid = 17.5+35(0.6)=38.50
Q: how can 14=F and then change to 14=0.8F?

Many thanks!!
[Reveal] Spoiler: OA
Expert Post
1 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 34817
Followers: 6476

Kudos [?]: 82535 [1] , given: 10107

Re: A farmer spent $35 on feed for chickens and goats. He spent [#permalink]

Show Tags

New post 21 Apr 2012, 11:41
1
This post received
KUDOS
Expert's post
Welcome to GMAT Club. Below is a solution for your question.

A farmer spent $35 on feed for chickens and goats. He spent 40% money on chicken feed, which he bought at a 20% discount off the full price, and spent the rest on goat feed, which he bought at full price. If the farmer had paid full price for both the chicken feed and the goat feed, what amount would he have spent on the chicken feed and goat feed combined?
A. $37.80
B. $38.50
C. $39.20
D. $39.50
E. $40.60

A farmer spent 40% money on chicken feed, so he spent 0.4*$35=$14 on chicken feed, thus he spent the remaining 35-14=$21 on goat feed.

Now, since he bought chicken feed at a 20% discount then the original price of it was x*0.8=$14 --> x=$17.5.

Therefore if the farmer had paid full price for both the chicken feed and the goat feed, then he would he have spent 17.5+21=$38.5.

Answer: B.

Hope it's clear.
_________________

New to the Math Forum?
Please read this: All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Intern
Intern
avatar
Joined: 05 Apr 2012
Posts: 12
Followers: 0

Kudos [?]: 4 [0], given: 3

Re: A farmer spent $35 on feed for chickens and goats. He spent [#permalink]

Show Tags

New post 21 Apr 2012, 15:30
Thank you very much Bunuel. It is clear now and the OA explanation must have a typo then.
However, why can't I put the 80% (20% discount) in the equation in the first place but rather have to get the 40% portion first and then obtain the before-discount price? The right approach makes great sense but if I'm faced with similar questions, I may set up the equation by incorporating all the factors again although that won't lead to the right answer.

thank you for your time!
Expert Post
1 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 34817
Followers: 6476

Kudos [?]: 82535 [1] , given: 10107

Re: A farmer spent $35 on feed for chickens and goats. He spent [#permalink]

Show Tags

New post 21 Apr 2012, 15:39
1
This post received
KUDOS
Expert's post
lamania wrote:
Thank you very much Bunuel. It is clear now and the OA explanation must have a typo then.
However, why can't I put the 80% (20% discount) in the equation in the first place but rather have to get the 40% portion first and then obtain the before-discount price? The right approach makes great sense but if I'm faced with similar questions, I may set up the equation by incorporating all the factors again although that won't lead to the right answer.

thank you for your time!


You can write one equation right away I just broke down the solution into several steps to make it easier. If interested here it is: 0.4*35/0.8+0.6*35=38.5. Notice that you should divide 0.4*35 by 0.8 to get original price and not multiply.
_________________

New to the Math Forum?
Please read this: All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Intern
Intern
avatar
Joined: 19 Apr 2012
Posts: 28
Followers: 0

Kudos [?]: 3 [0], given: 8

Re: A farmer spent $35 on feed for chickens and goats. He spent [#permalink]

Show Tags

New post 22 Apr 2012, 09:32
As always my question. This questin is quite easy but a lot of work to write and to calculate. I would suggest it is a question between 600 - 700 ? Without a calculator it is very time consuming.
Intern
Intern
avatar
Joined: 07 Apr 2012
Posts: 2
Followers: 0

Kudos [?]: 0 [0], given: 0

Re: A farmer spent $35 on feed for chickens and goats. He spent [#permalink]

Show Tags

New post 22 Apr 2012, 09:56
guys here is an easier way:
Let the farmer had 100 to spend.
He spent 40 on chickens and 60 on goats.
now actual price of chicken feed without discount
x-20%x=40
0.8x=40 or x=50
So without discount he would have spent 50+60=110
Now 110 for 100
For 35 it is 110/100*35=38.5

Posted from my mobile device Image
GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 09 Sep 2013
Posts: 11653
Followers: 527

Kudos [?]: 141 [0], given: 0

Premium Member
Re: A farmer spent $35 on feed for chickens and goats. He spent [#permalink]

Show Tags

New post 08 Jul 2016, 04:27
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.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

Director
Director
User avatar
Joined: 18 Oct 2014
Posts: 915
Location: United States
GMAT 1: 660 Q49 V31
GPA: 3.98
Followers: 80

Kudos [?]: 172 [0], given: 69

GMAT ToolKit User CAT Tests
Re: A farmer spent $35 on feed for chickens and goats. He spent [#permalink]

Show Tags

New post 08 Jul 2016, 05:09
lamania wrote:
A farmer spent $35 on feed for chickens and goats. He spent 40% money on chicken feed, which he bought at a 20% discount off the full price, and spent the rest on goat feed, which he bought at full price. If the farmer had paid full price for both the chicken feed and the goat feed, what amount would he have spent on the chicken feed and goat feed combined?

A. $37.80
B. $38.50
C. $39.20
D. $39.50
E. $40.60



He spent 40% of 35 on chicken feed, i.e 35*40/100= 14

This $14 was 80% (He got 20% discount), So the actual price without discount was= 14*100/80= 17.5

Amount spent on goat feed= 35-14= 21

Total price without discount= 21+17.5= 38.5

B is the answer
_________________

I welcome critical analysis of my post!! That will help me reach 700+

Re: A farmer spent $35 on feed for chickens and goats. He spent   [#permalink] 08 Jul 2016, 05:09
    Similar topics Author Replies Last post
Similar
Topics:
3 Experts publish their posts in the topic Bert left the house with N dollars. He spent 1/4 of this at the hardw Bunuel 5 03 Mar 2015, 07:13
1 If a farmer sells 15 of his chickens, his stock of feed will gmatgeek 1 12 Dec 2012, 13:43
7 Experts publish their posts in the topic If a farmer sells 15 of his chickens, his stock of feed will keiraria 7 01 May 2012, 14:53
33 Experts publish their posts in the topic If the farmer sells 75 of his chickens, his stock of feed slingfox 15 25 Oct 2009, 02:41
8 Experts publish their posts in the topic Yesterday each of the 35 members of a certain task force spent some ti tenaman10 6 29 Mar 2009, 10:05
Display posts from previous: Sort by

A farmer spent $35 on feed for chickens and goats. He spent

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group and phpBB SEO

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®.