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

It is currently 16 Oct 2019, 20:37

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

Working alone at a constant rate, Machine A can produce 15 widgets in

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

Hide Tags

Find Similar Topics 
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 58381
Working alone at a constant rate, Machine A can produce 15 widgets in  [#permalink]

Show Tags

New post 18 Jan 2019, 01:10
00:00
A
B
C
D
E

Difficulty:

  35% (medium)

Question Stats:

69% (02:11) correct 31% (02:21) wrong based on 62 sessions

HideShow timer Statistics

Working alone at a constant rate, Machine A can produce 15 widgets in 2 minutes. Working alone at a constant rate, Machine B can produce 20 widgets in 3 minutes. If the two machines start working at the same time, after how many minutes will Machine A have produced 40 more widgets than Machine B?

A 12
B 24
C 36
D 48
E 60

_________________
GMAT Club Legend
GMAT Club Legend
User avatar
D
Joined: 18 Aug 2017
Posts: 5009
Location: India
Concentration: Sustainability, Marketing
GPA: 4
WE: Marketing (Energy and Utilities)
GMAT ToolKit User Premium Member
Re: Working alone at a constant rate, Machine A can produce 15 widgets in  [#permalink]

Show Tags

New post 18 Jan 2019, 08:09
Bunuel wrote:
Working alone at a constant rate, Machine A can produce 15 widgets in 2 minutes. Working alone at a constant rate, Machine B can produce 20 widgets in 3 minutes. If the two machines start working at the same time, after how many minutes will Machine A have produced 40 more widgets than Machine B?

A 12
B 24
C 36
D 48
E 60


rate for A = 15/2
rate for B = 20/3

solve using answer options we see
that at 48 mins ; A would have made 40 more widgets than B
15*48/2 = 360
20*48/3 = 320

IMO D
Senior Manager
Senior Manager
User avatar
P
Joined: 15 Feb 2018
Posts: 365
Premium Member
Re: Working alone at a constant rate, Machine A can produce 15 widgets in  [#permalink]

Show Tags

New post 18 Jan 2019, 20:26
Working alone at a constant rate, Machine A can produce 15 widgets in 2 minutes.
Machine A rate: \(\frac{15 (widgets)}{2 (minutes)}\)

Working alone at a constant rate, Machine B can produce 20 widgets in 3 minutes.
Machine B rate:\(\frac{20 (widgets)}{3 (minutes)}\)

If the two machines start working at the same time, after how many minutes will Machine A have produced 40 more widgets than Machine B?
rate·time=work completed
We have the respective rates from above.
Machine A and B both work for the same time (we'll denote this time with x).
We know the work completed is a difference of 40

Machine A Rate·x - Machine B Rate·x=40 widgets
\(\frac{15 (widgets)}{2 (minutes)}·x - \frac{20 (widgets)}{3 (minutes)}·x=40 (widgets)\)
eliminate units for simplicity. Just remember x will be units of time
\(\frac{15x}{2}-\frac{20x}{3}=40\)
\(\frac{45x}{6}-\frac{40}{6}=40\)
\(\frac{5x}{6}=40\)
5x=240
x=48 minutes

D
GMAT Club Bot
Re: Working alone at a constant rate, Machine A can produce 15 widgets in   [#permalink] 18 Jan 2019, 20:26
Display posts from previous: Sort by

Working alone at a constant rate, Machine A can produce 15 widgets in

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





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