DS problem

BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

This topic has expert replies

Post new topic Post Reply

Previous Topic Next Topic

phoenix9801: Master | Next Rank: 500 Posts; Posts: 190; Joined: Thu Jan 14, 2010 8:29 pm; Thanked: 2 times

DS problem

by phoenix9801 » Fri May 25, 2012 2:25 am

Hi, I see before with a friend of mine and was wondering if any one knew how to solve? Looked similar to gmat question they might ask as Data Sufficiency. Can anyone please explain using plugging in numbers as simple as possible. Thanks.

Item F costs three times as much as item G, and item H cost $4 more than one-third the price of item G.

....Quantity A..................Quantity B

The Cost of Item F..........The Cost of item H

a) Quantity A is greater
b) Quantity B is Greater
c) the two quantity are equal
d) the relationship cannot be determined from the information given

Quote

Source: Beat The GMAT — Problem Solving | Fri May 25, 2012 2:25 am

eagleeye: Legendary Member; Posts: 520; Joined: Sat Apr 28, 2012 9:12 pm; Thanked: 339 times; Followed by:49 members; GMAT Score:770

by eagleeye » Fri May 25, 2012 4:11 am

Hey Phoenix9801:

Let the price of Item G be G, then we are given:
A = 3G;
B = 4+G/3;

Now I can tell from just this that the relationship can't be determined from this info, but let me show you using numbers. Let's equate the two (A and B) first.
A=B => 3G = 4+G/3 => 3G-G/3 = 4 => 8G/3 = 4 => G = 3/2 = 1.5

Let me know if this helps

Now if G = 1.5 ; A=3G = 4.5; B = 4+G/3= 4.5 ; then A and B are equal.
If G < 1.5; let G = 0; then A=0; B = 4; then B is greater than A.
If G > 1.5[/i]; let G = 3; A=9; B = 4+3/3 = 5; then A is greater than B.

So clearly as G ranges from 0 to 1.5 to 4; we get three different answers. Hence correct answer is D

Let me know if this helps

Quote

aneesh.kg: Master | Next Rank: 500 Posts; Posts: 385; Joined: Mon Apr 16, 2012 8:40 am; Location: Pune, India; Thanked: 186 times; Followed by:29 members

by aneesh.kg » Fri May 25, 2012 8:30 am

phoenix9801 wrote:Hi, I see before with a friend of mine and was wondering if any one knew how to solve? Looked similar to gmat question they might ask as Data Sufficiency. Can anyone please explain using plugging in numbers as simple as possible. Thanks.

Item F costs three times as much as item G, and item H cost $4 more than one-third the price of item G.

....Quantity A..................Quantity B

The Cost of Item F..........The Cost of item H

a) Quantity A is greater
b) Quantity B is Greater
c) the two quantity are equal
d) the relationship cannot be determined from the information given

This looks like a GRE problem.
Let the cost of G be $1.
Cost of F = 3*1 = $3
Cost of H = 4 + (1/3)*1 = $4.33

H > F

Let the cost of G be $100.
Cost of F = 3*100 = $300.
Cost of H = 4 + (1/3)*(100) = 33.33 + 4 = 37.33

F > H

Relationship depends of the magnitude of quantity G.

[spoiler](D)[/spoiler] is the correct answer.

This can be understood better by plotting F and H, which are straight lines w.r.t. G, using co-ordinate geometry as shown below:

Last edited by aneesh.kg on Fri May 25, 2012 8:48 am, edited 2 times in total.

Aneesh Bangia
GMAT Math Coach
[email protected]

GMATPad:
Facebook Page: https://www.facebook.com/GMATPad

Quote

GMATGuruNY: GMAT Instructor; Posts: 15539; Joined: Tue May 25, 2010 12:04 pm; Location: New York, NY; Thanked: 13060 times; Followed by:1906 members; GMAT Score:790

by GMATGuruNY » Fri May 25, 2012 8:30 am

phoenix9801 wrote:Hi, I see before with a friend of mine and was wondering if any one knew how to solve? Looked similar to gmat question they might ask as Data Sufficiency. Can anyone please explain using plugging in numbers as simple as possible. Thanks.

Item F costs three times as much as item G, and item H cost $4 more than one-third the price of item G.

....Quantity A..................Quantity B

The Cost of Item F..........The Cost of item H

a) Quantity A is greater
b) Quantity B is Greater
c) the two quantity are equal
d) the relationship cannot be determined from the information given

Let G=3.
Then H = 4 + (1/3)G = 4 + (1/3)3 = 5.
F = 3G = 3*3 = 9.
F > H.

Let G=1.
Then H = 4 + (1/3)G = 4 + (1/3)1 = 4 1/3.
F = 3G = 3*1 = 3.
F < H.

The correct answer is D.

Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.

As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.

For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3

Quote

ronnie1985: Legendary Member; Posts: 626; Joined: Fri Dec 23, 2011 2:50 am; Location: Ahmedabad; Thanked: 31 times; Followed by:10 members