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

 It is currently 21 Oct 2019, 14:41

### 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

# A metallic cubical box was hammered and moulded into a rectangular box

Author Message
Senior PS Moderator
Joined: 26 Feb 2016
Posts: 3335
Location: India
GPA: 3.12
A metallic cubical box was hammered and moulded into a rectangular box  [#permalink]

### Show Tags

14 Apr 2019, 02:47
1
1
00:00

Difficulty:

75% (hard)

Question Stats:

57% (02:18) correct 43% (01:56) wrong based on 82 sessions

### HideShow timer Statistics

A metallic cubical box was hammered and moulded into a rectangular box such that the only change was that the breadth got tripled. What was the percentage change in total surface area?

A. 33.33%
B. 66.67%
C. 100%
D. 133.33%
E. 200%

Source: Experts Global

_________________
You've got what it takes, but it will take everything you've got
Senior Manager
Joined: 05 Jul 2018
Posts: 424
Location: India
Concentration: General Management, Technology
GMAT 1: 600 Q47 V26
GRE 1: Q162 V149
GPA: 3.6
WE: Information Technology (Consulting)
A metallic cubical box was hammered and moulded into a rectangular box  [#permalink]

### Show Tags

Updated on: 16 Apr 2019, 01:36
2
Although the scenario is too hypothetical to think of, wherein just one side of the new cuboid has tripled after hammering and everything else remains unchanged, yet considering the hypothesis to be real the answer goes as below.

Tripling one side of the cuboid the surface area becomes 14x of the original surface area 6x.

Percent Change in Volume=$$\frac{8x}{6x}*100$$ = 133.33%

_________________
Appreciate any KUDOS given !

MY MBA RESOURCES:

4000 Official Verbal Question | 3700 Official quant questions

Originally posted by saukrit on 14 Apr 2019, 03:06.
Last edited by saukrit on 16 Apr 2019, 01:36, edited 1 time in total.
Manager
Joined: 04 Sep 2016
Posts: 66
Location: Germany
GPA: 3
A metallic cubical box was hammered and moulded into a rectangular box  [#permalink]

### Show Tags

15 Apr 2019, 02:10
2
themindful wrote:
Although the scenario is too hypothetical to think of, wherein just one side of the new cuboid has tripled after hammering and everything else remains unchanged, yet considering the hypothesis to be real the answer goes as below.

Tripling one side of the cuboid the volume become 3x of the original volume x.

Change in Volume=$$\frac{(3x-x)}{x}*100$$ = 200%

I think the answer is D. They have asked change in surface area and not volume

Posted from my mobile device
_________________
Proud Wildling

The three great essentials to achieve anything worthwhile are, first, hard work; second, stick-to-itiveness; third, common sense."
Intern
Joined: 13 Jul 2018
Posts: 13
Location: India
Schools: EDHEC
GPA: 2.49
Re: A metallic cubical box was hammered and moulded into a rectangular box  [#permalink]

### Show Tags

15 Apr 2019, 12:28
Hi the question stem asks % change in surface area.

Posted from my mobile device
Intern
Joined: 13 Jul 2018
Posts: 13
Location: India
Schools: EDHEC
GPA: 2.49
Re: A metallic cubical box was hammered and moulded into a rectangular box  [#permalink]

### Show Tags

15 Apr 2019, 12:30
Will the answer be option D

Posted from my mobile device
Senior Manager
Joined: 05 Jul 2018
Posts: 424
Location: India
Concentration: General Management, Technology
GMAT 1: 600 Q47 V26
GRE 1: Q162 V149
GPA: 3.6
WE: Information Technology (Consulting)
Re: A metallic cubical box was hammered and moulded into a rectangular box  [#permalink]

### Show Tags

16 Apr 2019, 01:39
Sanjeetgujrall wrote:
themindful wrote:
Although the scenario is too hypothetical to think of, wherein just one side of the new cuboid has tripled after hammering and everything else remains unchanged, yet considering the hypothesis to be real the answer goes as below.

Tripling one side of the cuboid the volume become 3x of the original volume x.

Change in Volume=$$\frac{(3x-x)}{x}*100$$ = 200%

I think the answer is D. They have asked change in surface area and not volume

Posted from my mobile device

Thanks for highlighting. Updated my response. My bad
_________________
Appreciate any KUDOS given !

MY MBA RESOURCES:

4000 Official Verbal Question | 3700 Official quant questions

Experts' Global Representative
Joined: 19 Feb 2010
Posts: 235
A metallic cubical box was hammered and moulded into a rectangular box  [#permalink]

### Show Tags

19 Jul 2019, 04:18
Interestingly, some students wrote to us saying that if the width is changed, the volume also changed and that is not possible by hammering (as volume of the solid must remain constant). The mistake in that approach is that one is confusing volume of the "box" (not a solid, as such) with the volume of the "metal" (or solid). Imagine, the box is empty inside and practically, the volume of the box is the volume of the empty space and not the volume of the metal enclosing the empty space
_________________
Intern
Joined: 24 Aug 2017
Posts: 6
Re: A metallic cubical box was hammered and moulded into a rectangular box  [#permalink]

### Show Tags

21 Jul 2019, 09:41
Tripling one side of the cuboid the surface area becomes 14x of the original surface area 6x.
How??? Can you explain???

Posted from my mobile device
Intern
Joined: 24 Oct 2017
Posts: 32
Location: India
GMAT 1: 710 Q48 V39
GPA: 3.39
Re: A metallic cubical box was hammered and moulded into a rectangular box  [#permalink]

### Show Tags

21 Jul 2019, 22:44
1
surface area = 2(Lw+wh+Lh)
original S.A. = 6a^2
new = 2(a*3a + 3a*a + a*a) = 14a^2

%change = (14a^2 - 6a^2)/ 6a^2 *100% = (8/6)*100 = 133.33% (D)
Intern
Joined: 24 Aug 2017
Posts: 6
A metallic cubical box was hammered and moulded into a rectangular box  [#permalink]

### Show Tags

21 Jul 2019, 22:48
Saurabhminocha wrote:
surface area = 2(Lw+wh+Lh)
original S.A. = 6a^2
new = 2(a*3a + 3a*a + a*a) = 14a^2

%change = (14a^2 - 6a^2)/ 6a^2 *100% = (8/6)*100 = 133.33% (D)

thanks a lot...I get it now.

Posted from my mobile device
A metallic cubical box was hammered and moulded into a rectangular box   [#permalink] 21 Jul 2019, 22:48
Display posts from previous: Sort by