Author 
Message 
TAGS:

Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 44656

Of the land owned by a farmer, 90 percent was cleared for planting. Of [#permalink]
Show Tags
15 Oct 2015, 22:04
Question Stats:
80% (01:22) correct 20% (01:22) wrong based on 715 sessions
HideShow timer Statistics
Of the land owned by a farmer, 90 percent was cleared for planting. Of the cleared land, 40 percent was planted with soybeans and 50 percent of the cleared land was planted with wheat. If the remaining 720 acres of cleared land was planted with corn, how many acres did the farmer own? (A) 5,832 (B) 6,480 (C) 7,200 (D) 8,000 (E) 8,889 Kudos for a correct solution.
Official Answer and Stats are available only to registered users. Register/ Login.
_________________
New to the Math Forum? Please read this: Ultimate GMAT Quantitative Megathread  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? Extrahard Quant Tests with Brilliant Analytics



Director
Joined: 10 Mar 2013
Posts: 563
Location: Germany
Concentration: Finance, Entrepreneurship
GPA: 3.88
WE: Information Technology (Consulting)

Re: Of the land owned by a farmer, 90 percent was cleared for planting. Of [#permalink]
Show Tags
15 Oct 2015, 23:14
1
This post received KUDOS
1
This post was BOOKMARKED
Bunuel wrote: Of the land owned by a farmer, 90 percent was cleared for planting. Of the cleared land, 40 percent was planted with soybeans and 50 percent of the cleared land was planted with wheat. If the remaining 720 acres of cleared land was planted with corn, how many acres did the farmer own?
(A) 5,832 (B) 6,480 (C) 7,200 (D) 8,000 (E) 8,889
Kudos for a correct solution. 40% od 90% = 36%, 50% 0f 90% = 45% so the remaining 904536=9%=720 acres or 10% of 90%=9% > 720/9*100=80o0 acres Answer (D)
_________________
When you’re up, your friends know who you are. When you’re down, you know who your friends are.
Share some Kudos, if my posts help you. Thank you !
800Score ONLY QUANT CAT1 51, CAT2 50, CAT3 50 GMAT PREP 670 MGMAT CAT 630 KAPLAN CAT 660



Verbal Forum Moderator
Status: Greatness begins beyond your comfort zone
Joined: 08 Dec 2013
Posts: 1963
Location: India
Concentration: General Management, Strategy
GPA: 3.2
WE: Information Technology (Consulting)

Re: Of the land owned by a farmer, 90 percent was cleared for planting. Of [#permalink]
Show Tags
16 Oct 2015, 02:14
3
This post received KUDOS
1
This post was BOOKMARKED
Percentage cleared for planting = 90 Soybean = 40% of 90 = 36 % of total Wheat = 50 % of 90 =45 % of total Corn = 10 % of 90 = 9 % of total Since 9% of total = 720 acres Therefore , total land = 720/9 * 100 = 8000 acres Answer D
_________________
When everything seems to be going against you, remember that the airplane takes off against the wind, not with it.  Henry Ford The Moment You Think About Giving Up, Think Of The Reason Why You Held On So Long +1 Kudos if you find this post helpful



Manager
Joined: 02 Jul 2015
Posts: 106

Re: Of the land owned by a farmer, 90 percent was cleared for planting. Of [#permalink]
Show Tags
16 Oct 2015, 02:40
1
This post received KUDOS
IMO 8000
9 out of 100 corresponds to 720 out of 8000.



Manager
Joined: 26 Dec 2012
Posts: 146
Location: United States
Concentration: Technology, Social Entrepreneurship
WE: Information Technology (Computer Software)

Re: Of the land owned by a farmer, 90 percent was cleared for planting. Of [#permalink]
Show Tags
16 Oct 2015, 18:52
1
This post received KUDOS
Let farmer has X land; Cleaned =.9 x out of .9 x 10% is 720 ; therefore .09x=720 => x=8000
Hence answer is D
Thanks



Manager
Joined: 13 Mar 2013
Posts: 174
Location: United States
Concentration: Leadership, Technology
GPA: 3.5
WE: Engineering (Telecommunications)

Re: Of the land owned by a farmer, 90 percent was cleared for planting. Of [#permalink]
Show Tags
16 Oct 2015, 20:58
1
This post received KUDOS
Of the land owned by a farmer, 90 percent was cleared for planting. Of the cleared land, 40 percent was planted with soybeans and 50 percent of the cleared land was planted with wheat. If the remaining 720 acres of cleared land was planted with corn, how many acres did the farmer own? (A) 5,832 (B) 6,480 (C) 7,200 (D) 8,000 (E) 8,889 For this type of Question its always better to go by option and elimination plays a key role here . As per the Q  out of the total land  90% was cleared for planting . now see the option  only B,C, D will give you a integer value .When we do 90% of total Area. hence A,E can be eliminated . Option B  6480 * (90/100) = 5832 5832 * ( 40/100 ) = wont give us a integer value . Hence can be eliminated . Option C and D left . Now see option D is good number to start with because its value .( 8000) When we apply 8000( 90/100) = 7200 (50/100) = 3600 7200(40/100)= 2880 Now sum them = 2880 + 3600 = 6480 If the remaining 720 acres of cleared land was planted with corn . This remaining area comes from 7200  6480 = 720 . Hence the condition got satisfied . Ans is D .
_________________
Regards ,



Target Test Prep Representative
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 2480
Location: United States (CA)

Re: Of the land owned by a farmer, 90 percent was cleared for planting. Of [#permalink]
Show Tags
02 May 2016, 08:55
2
This post received KUDOS
Expert's post
1
This post was BOOKMARKED
Bunuel wrote: Of the land owned by a farmer, 90 percent was cleared for planting. Of the cleared land, 40 percent was planted with soybeans and 50 percent of the cleared land was planted with wheat. If the remaining 720 acres of cleared land was planted with corn, how many acres did the farmer own?
(A) 5,832 (B) 6,480 (C) 7,200 (D) 8,000 (E) 8,889
Kudos for a correct solution. Solution: We can start by letting T = the total land owned by the farmer. Since 90% was cleared for farming we can say: 0.9T = cleared for farming We are next given that of the cleared land, 40 percent was planted with soybeans. This can be represented as: 0.4(0.9T) = planted with soybeans 0.36T = planted with soybeans Next we are given that 50 percent of the cleared land was planted with wheat. This can be represented as: 0.5(0.9T) = 0.45T Finally, we are given that the remaining 720 acres of cleared land was planted with corn. Thus, we can create the following equation: 0.36T + 0.45T + 720 = 0.9T 0.81T + 720 = 0.9T 720 = 0.09T 72,000 = 9T T = 8,000 Answer: D
_________________
Scott WoodburyStewart
Founder and CEO
GMAT Quant SelfStudy Course
500+ lessons 3000+ practice problems 800+ HD solutions



Director
Status: Professional GMAT Tutor
Affiliations: AB, cum laude, Harvard University (Class of '02)
Joined: 10 Jul 2015
Posts: 606
Location: United States (CA)
Age: 38
GMAT 1: 770 Q47 V48 GMAT 2: 730 Q44 V47 GMAT 3: 750 Q50 V42
GRE 1: 337 Q168 V169
WE: Education (Education)

Re: Of the land owned by a farmer, 90 percent was cleared for planting. Of [#permalink]
Show Tags
10 May 2016, 17:55
2
This post received KUDOS
Attached is a visual that should help.
Attachments
Screen Shot 20160510 at 5.48.46 PM.png [ 67.68 KiB  Viewed 7097 times ]
_________________
Harvard grad and 99% GMAT scorer, offering expert, private GMAT tutoring and coaching, both inperson (San Diego, CA, USA) and online worldwide, since 2002.
One of the only known humans to have taken the GMAT 5 times and scored in the 700s every time (700, 710, 730, 750, 770), including verified section scores of Q50 / V47, as well as personal bests of 8/8 IR (2 times), 6/6 AWA (4 times), 50/51Q and 48/51V (1 question wrong).
You can download my official testtaker score report (all scores within the last 5 years) directly from the Pearson Vue website: https://tinyurl.com/y8zh6qby Date of Birth: 09 December 1979.
GMAT Action Plan  McElroy Tutoring



Manager
Status: One Last Shot !!!
Joined: 04 May 2014
Posts: 249
Location: India
Concentration: Marketing, Social Entrepreneurship
GMAT 1: 630 Q44 V32 GMAT 2: 680 Q47 V35

Re: Of the land owned by a farmer, 90 percent was cleared for planting. Of [#permalink]
Show Tags
10 May 2016, 19:58
1
This post received KUDOS
(10% of (90% of total land)) is 720 \(0.1 * 0.9 * X = 720\) \(X = 8000\) Option D
_________________
One Kudos for an everlasting piece of knowledge is not a bad deal at all...
 Twenty years from now you will be more disappointed by the things you didn't do than by the ones you did do. So throw off the bowlines. Sail away from the safe harbor. Catch the trade winds in your sails. Explore. Dream. Discover. Mark Twain



Intern
Joined: 01 Feb 2016
Posts: 4
Location: Honduras
Concentration: Operations, Economics
GPA: 3.3
WE: Supply Chain Management (Transportation)

Re: Of the land owned by a farmer, 90 percent was cleared for planting. Of [#permalink]
Show Tags
21 Jun 2016, 11:12
I understand it the following way: 0.40(90)+0.50(90)+720=0.90x 2880+3600+720=0.90x 7200=0.90x \(\frac{7200}{0.90}\)=x 8000=x



Manager
Joined: 20 Mar 2015
Posts: 62

Of the land owned by a farmer, 90 percent was cleared for planting. Of [#permalink]
Show Tags
24 Jun 2016, 04:55
Bunuel wrote: Of the land owned by a farmer, 90 percent was cleared for planting. Of the cleared land, 40 percent was planted with soybeans and 50 percent of the cleared land was planted with wheat. If the remaining 720 acres of cleared land was planted with corn, how many acres did the farmer own?
(A) 5,832 (B) 6,480 (C) 7,200 (D) 8,000 (E) 8,889
Kudos for a correct solution. Suppose the total land was 100. Then, 90% of 100 = 90. Of the 90, 40%(36) of land was used for soyabeans, 50%(45) was for wheat. Remaining land portion of 90 is 9. According to question 9 equals 720. By unitary method. If; 9(land) = 720 then; 100(land) =x(what). By cross multiplication. x = \(720*100/9\) = 8000.D.



Intern
Joined: 08 Oct 2016
Posts: 1

Re: Of the land owned by a farmer, 90 percent was cleared for planting. Of [#permalink]
Show Tags
13 Nov 2016, 23:23
Hi,
Is this a right approach [or an unnecessarily longer one?]
In the cleared land : 720 is 10% Hence, 720*4 = 2880 is 40% and, 720*5 = 3600 is 50%
Adding all these the 90% cleared land turns out to be 7200, the remaining has to be 800. Hence 7200+800 = 8000 > Answer D.



Senior Manager
Joined: 25 Mar 2013
Posts: 267
Location: United States
Concentration: Entrepreneurship, Marketing
GPA: 3.5

Re: Of the land owned by a farmer, 90 percent was cleared for planting. Of [#permalink]
Show Tags
22 Dec 2016, 14:37
0.4 x 0.9X = 0.36X = Soybean 0.5 x 0.9X = 0.45X = Wheat 0.36x + 0.45x + 720 = 0.9x 0.81x + 720 = 0.9x x = 8000 D
_________________
I welcome analysis on my posts and kudo +1 if helpful. It helps me to improve my craft.Thank you



EMPOWERgmat Instructor
Status: GMAT Assassin/CoFounder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 11515
Location: United States (CA)
GRE 1: 340 Q170 V170

Re: Of the land owned by a farmer, 90 percent was cleared for planting. Of [#permalink]
Show Tags
03 Feb 2018, 16:36
Hi All, This question can be solved by TESTing THE ANSWERS. From the prompt, we know that we're going to be doing a number of small calculations AND we're going to end with 720 acres remaining for corn. Since we're asked for the total number of acres, and the answers are all numbers, we just have to work until we find the one that matches what we've been told. In these situations, it's often best to start with Answer B or D. Between those 2 options, D looks 'nicer'/easier, so let's start there. IF....there were 8000 total acres... 90% was cleared for planting = (.9)(8000) = 7200 acres for planting Of that land, 40% was soybeans = (4.)(7200) = 2880 acres 50% was wheat = (.5)(7200) = 3600 2880 + 3600 = 6480 7200  6480 = 720 > this is an exact match for what we were told, so this MUST be the answer. Final Answer: GMAT assassins aren't born, they're made, Rich
_________________
760+: Learn What GMAT Assassins Do to Score at the Highest Levels Contact Rich at: Rich.C@empowergmat.com
Rich Cohen
CoFounder & GMAT Assassin
Special Offer: Save $75 + GMAT Club Tests Free
Official GMAT Exam Packs + 70 Pt. Improvement Guarantee www.empowergmat.com/
***********************Select EMPOWERgmat Courses now include ALL 6 Official GMAC CATs!***********************




Re: Of the land owned by a farmer, 90 percent was cleared for planting. Of
[#permalink]
03 Feb 2018, 16:36






