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

It is currently 18 May 2019, 23:35

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.

Close

Request Expert Reply

Confirm Cancel

In a certain box of of widgets there are only brass widgets and iron

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

Hide Tags

 
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 55150
In a certain box of of widgets there are only brass widgets and iron  [#permalink]

Show Tags

New post 10 Sep 2017, 05:49
00:00
A
B
C
D
E

Difficulty:

  15% (low)

Question Stats:

89% (01:42) correct 11% (03:07) wrong based on 44 sessions

HideShow timer Statistics

In a certain box of of widgets there are only brass widgets and iron widgets. If 42 of the widgets are brass and 14 are iron, what is the total weight, in kilograms of the box?

(1) The weight of seven brass widgets is three times the weight of an iron widget.
(2) The total weight of a brass widget and five iron widgets is 38 kilograms.

_________________
Intern
Intern
avatar
B
Joined: 12 Dec 2016
Posts: 10
Location: Russian Federation
GMAT 1: 660 Q49 V31
GPA: 3
Re: In a certain box of of widgets there are only brass widgets and iron  [#permalink]

Show Tags

New post 10 Sep 2017, 07:14
Lets say that
b - weight of the brass widget
i - weight of iron widget

The question is 42 * b + 14 * i = ?

Let's express given statements with formulas:
1) 7 * b = 3 * i
2) b + 5 *i = 38
In both we can express one variable through another and substitute in the equation, but as the remaining variable is unknown we can't calculate the total weight.
Both are NS


Taking statements together, we can solve.
Multiply second statement by 7
7 * b + 35 * i = 7 * 38
Substitute by the expression from the first statement (7 * b = 3 * i)
3 * i + 35 * i = 7 * 38
38 * i = 7 * 38 => i = 7
b = 3 * i / 7 = > b = 3
Total weight will be 42 * 3 + 14 * 7 = 224

Answer C
Manager
Manager
User avatar
G
Joined: 27 Dec 2016
Posts: 232
Concentration: Marketing, Social Entrepreneurship
GPA: 3.65
WE: Marketing (Education)
Reviews Badge
Re: In a certain box of of widgets there are only brass widgets and iron  [#permalink]

Show Tags

New post 10 Sep 2017, 11:07
Zarevl wrote:
Lets say that
b - weight of the brass widget
i - weight of iron widget

The question is 42 * b + 14 * i = ?

Let's express given statements with formulas:
1) 7 * b = 3 * i
2) b + 5 *i = 38
In both we can express one variable through another and substitute in the equation, but as the remaining variable is unknown we can't calculate the total weight.
Both are NS


Taking statements together, we can solve.
Multiply second statement by 7
7 * b + 35 * i = 7 * 38
Substitute by the expression from the first statement (7 * b = 3 * i)
3 * i + 35 * i = 7 * 38
38 * i = 7 * 38 => i = 7
b = 3 * i / 7 = > b = 3
Total weight will be 42 * 3 + 14 * 7 = 224

Answer C


Buddy, in statement 2, we indeed have enough information to get the value of iron and brass widget..
\(B+5I=38\) --> \(B=38-5I\), we can substitute in \(42B+14I\) equation.

Am I correct?
_________________
There's an app for that - Steve Jobs.
Manager
Manager
User avatar
B
Joined: 19 Jul 2017
Posts: 85
Location: India
Concentration: General Management, Strategy
GPA: 3.5
Re: In a certain box of of widgets there are only brass widgets and iron  [#permalink]

Show Tags

New post 11 Sep 2017, 00:29
Bunuel wrote:
In a certain box of of widgets there are only brass widgets and iron widgets. If 42 of the widgets are brass and 14 are iron, what is the total weight, in kilograms of the box?

(1) The weight of seven brass widgets is three times the weight of an iron widget.
(2) The total weight of a brass widget and five iron widgets is 38 kilograms.



S1:
Let I be weight of 1 Iron Widget.
Weight of 7 Brass = 3I
Weight of 42 Brass Widgets = 18I.
So total weight = 18I+14I. we dont what W is in kgs. So insufficient.

S2:
B+5I= 38
B= 38-5I;. Still not getting values of total widgets asked in the question. Insufficinet

Combining
42(38-5I)+14I=32I;
42(38-5I)=18I
7*(38-5I)=3I
7*38= 38 I;I=7;
Total Weight = 7*32= 224kgs;

ANs:C
Intern
Intern
avatar
B
Joined: 12 Dec 2016
Posts: 10
Location: Russian Federation
GMAT 1: 660 Q49 V31
GPA: 3
In a certain box of of widgets there are only brass widgets and iron  [#permalink]

Show Tags

New post 11 Sep 2017, 05:19
Buddy, in statement 2, we indeed have enough information to get the value of iron and brass widget..
\(B+5I=38\) --> \(B=38-5I\), we can substitute in \(42B+14I\) equation.

Am I correct?[/quote]

Sorry, no :-)
You expressed B in terms of I, but we still don't know the value of I

42 * B + 14 * I = ?
42 * (38 - 5 * I) + 14 * I = ?
42 * 38 - 42 * 5 * I + 14 * I
42*32 - 196 * I = ?
There are several possible values for I, so that this equation will give integer result.
GMAT Club Bot
In a certain box of of widgets there are only brass widgets and iron   [#permalink] 11 Sep 2017, 05:19
Display posts from previous: Sort by

In a certain box of of widgets there are only brass widgets and iron

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


Copyright

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

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

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®.