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

 It is currently 15 Feb 2019, 11:04

### 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

## Events & Promotions

###### Events & Promotions in February
PrevNext
SuMoTuWeThFrSa
272829303112
3456789
10111213141516
17181920212223
242526272812
Open Detailed Calendar
• ### \$450 Tuition Credit & Official CAT Packs FREE

February 15, 2019

February 15, 2019

10:00 PM EST

11:00 PM PST

EMPOWERgmat is giving away the complete Official GMAT Exam Pack collection worth \$100 with the 3 Month Pack (\$299)
• ### Free GMAT practice

February 15, 2019

February 15, 2019

10:00 PM EST

11:00 PM PST

Instead of wasting 3 months solving 5,000+ random GMAT questions, focus on just the 1,500 you need.

# The value of a diamond is proportional to the square of its weight. A

Author Message
TAGS:

### Hide Tags

Manager
Joined: 29 Nov 2018
Posts: 98
Concentration: Marketing, Strategy
The value of a diamond is proportional to the square of its weight. A  [#permalink]

### Show Tags

09 Feb 2019, 11:36
00:00

Difficulty:

45% (medium)

Question Stats:

60% (02:13) correct 40% (02:13) wrong based on 20 sessions

### HideShow timer Statistics

The value of a diamond is proportional to the square of its weight. A diamond weighing 4 gms falls and breaks into two pieces. What are the weights of the pieces if the value of the diamond reduces by 37.5%?

(A) 1 gm, 3 gm
(B) 1.5 gm, 2.5 gm
(C) 2 gm, 2 gm
(D) 1.2 gm, 2.8 gm
(E) 1.4 gm, 2.6 gm
Director
Joined: 09 Mar 2018
Posts: 903
Location: India
Re: The value of a diamond is proportional to the square of its weight. A  [#permalink]

### Show Tags

09 Feb 2019, 12:01
cfc198 wrote:
The value of a diamond is proportional to the square of its weight. A diamond weighing 4 gms falls and breaks into two pieces. What are the weights of the pieces if the value of the diamond reduces by 37.5%?

(A) 1 gm, 3 gm
(B) 1.5 gm, 2.5 gm
(C) 2 gm, 2 gm
(D) 1.2 gm, 2.8 gm
(E) 1.4 gm, 2.6 gm

v proportional to the square of its weight = w^2

Now value 16 is reduced by {375 *1/1000* 16} = 10

Now i need to get a 10
1+9 = 10

Only A does that
_________________

If you notice any discrepancy in my reasoning, please let me know. Lets improve together.

Quote which i can relate to.
Many of life's failures happen with people who do not realize how close they were to success when they gave up.

e-GMAT Representative
Joined: 04 Jan 2015
Posts: 2568
The value of a diamond is proportional to the square of its weight. A  [#permalink]

### Show Tags

Updated on: 13 Feb 2019, 21:28

Solution

Given:
• The value of a diamond is proportional to the square of its weight.
• A diamond weighing 4 gms falls and breaks into two pieces.
• The value of the diamond reduces by 37.5%.

To find:
• The weights of the two broken pieces.

Approach and Working:
Let us assume that original value V = 100.

As the value of a diamond is proportional to the square of its weight, we can say V/w^2 = constant
• As w = 4 and V = 100, V/w^2 = 100/16 = 25/4

Now, in the individual broken pieces also, this ratio will be maintained.
Considering the first option,
• If weights are 1 and 3, and corresponding values are V1 and V2, then
V1/1 = 25/4 indicates V1 = 25/4
V2/9 = 25/4 indicates V2 = 225/4

Therefore, new value = 25/4 + 225/4 = 250/4 = 62.5, which is 37.5% less than the original value.

Hence, the correct answer is option A.

_________________

| '4 out of Top 5' Instructors on gmatclub | 70 point improvement guarantee | www.e-gmat.com

Originally posted by EgmatQuantExpert on 10 Feb 2019, 04:55.
Last edited by EgmatQuantExpert on 13 Feb 2019, 21:28, edited 1 time in total.
SVP
Joined: 18 Aug 2017
Posts: 1770
Location: India
Concentration: Sustainability, Marketing
GPA: 4
WE: Marketing (Energy and Utilities)
Re: The value of a diamond is proportional to the square of its weight. A  [#permalink]

### Show Tags

10 Feb 2019, 08:53
1
cfc198 wrote:
The value of a diamond is proportional to the square of its weight. A diamond weighing 4 gms falls and breaks into two pieces. What are the weights of the pieces if the value of the diamond reduces by 37.5%?

(A) 1 gm, 3 gm
(B) 1.5 gm, 2.5 gm
(C) 2 gm, 2 gm
(D) 1.2 gm, 2.8 gm
(E) 1.4 gm, 2.6 gm

value 4 gms = 16
after fall its value = 16*.625 ~ 10

option A = 1^2 + 3^2 = 10
IMO A
_________________

If you liked my solution then please give Kudos. Kudos encourage active discussions.

Intern
Joined: 18 Jul 2018
Posts: 1
Re: The value of a diamond is proportional to the square of its weight. A  [#permalink]

### Show Tags

12 Feb 2019, 10:54
cfc198 wrote:
The value of a diamond is proportional to the square of its weight. A diamond weighing 4 gms falls and breaks into two pieces. What are the weights of the pieces if the value of the diamond reduces by 37.5%?

(A) 1 gm, 3 gm
(B) 1.5 gm, 2.5 gm
(C) 2 gm, 2 gm
(D) 1.2 gm, 2.8 gm
(E) 1.4 gm, 2.6 gm

_________
It is beneficial to see that 37.5% is equal to 3/8, and 8 is a factor of 16. Thus, computation becomes relatively simple.

4^2 = 16
16 x 3/8 = 6
16 - 6= 10

3^2=9 and 1^2= 1
9+1=10
The only solution that creates 10 is option A.
________
Hope this helps somebody!

All the best,
Rumi
Re: The value of a diamond is proportional to the square of its weight. A   [#permalink] 12 Feb 2019, 10:54
Display posts from previous: Sort by