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

 It is currently 19 Oct 2019, 21:22

### 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

# If all machines in a factory are equally efficient and 10 machines

Author Message
TAGS:

### Hide Tags

BSchool Forum Moderator
Joined: 29 Jan 2015
Posts: 1419
Location: India
WE: General Management (Non-Profit and Government)
If all machines in a factory are equally efficient and 10 machines  [#permalink]

### Show Tags

22 Aug 2018, 10:21
5
00:00

Difficulty:

15% (low)

Question Stats:

81% (01:45) correct 19% (02:27) wrong based on 102 sessions

### HideShow timer Statistics

If all machines in a factory are equally efficient and 10 machines take 8 seconds to produce 40 cans, how long will it take 12 machines to produce 600 cans?

A- 25 seconds
B- 50 seconds
C- 1 minute and 40 seconds
D- 2 minutes
E- 3 minutes and 20 seconds

_________________
If you liked my post, kindly give me a Kudos. Thanks.
Director
Joined: 20 Feb 2015
Posts: 762
Concentration: Strategy, General Management
Re: If all machines in a factory are equally efficient and 10 machines  [#permalink]

### Show Tags

22 Aug 2018, 13:10
rohan2345 wrote:
If all machines in a factory are equally efficient and 10 machines take 8 seconds to produce 40 cans, how long will it take 12 machines to produce 600 cans?

A- 25 seconds
B- 50 seconds
C- 1 minute and 40 seconds
D- 2 minutes
E- 3 minutes and 20 seconds

$$\frac{M1*D1*H1}{W1}$$ = $$\frac{M2*D2*H2}{W2}$$

substituting the values

$$\frac{10*8}{40}$$= $$\frac{12*t}{600}$$
t=100 seconds=1 minute 40 seconds
GMATH Teacher
Status: GMATH founder
Joined: 12 Oct 2010
Posts: 935
Re: If all machines in a factory are equally efficient and 10 machines  [#permalink]

### Show Tags

31 Aug 2018, 07:25
rohan2345 wrote:
If all machines in a factory are equally efficient and 10 machines take 8 seconds to produce 40 cans, how long will it take 12 machines to produce 600 cans?

A- 25 seconds
B- 50 seconds
C- 1 minute and 40 seconds
D- 2 minutes
E- 3 minutes and 20 seconds

Excellent opportunity to use UNITS CONTROL, one of our most powerful tools!

(The solution may seem excessively "sophisticated", but it works in much hard/high-level question scenarios!)

$$\boxed{10\,\,mach}\,\,\,\,\, \to \,\,\,\,\frac{{40\,\,{\text{cans}}}}{{8\,\,{\text{s}}}} = \boxed{\frac{{5\,\,{\text{cans}}}}{{1\,\,{\text{s}}}}\,\,\,\begin{array}{*{20}{c}} \nearrow \\ \nearrow \end{array}}$$

$$12\,\,mach\,\,,\,\,\,600\,\,cans\,\,\,\,\, \to \,\,\,\,?\,\,\,:\,\,\,{\text{time}}\,$$

$$12\,\,mach\,\,\,\, = \,\,\,\boxed{10\,\,mach}\,\,\left( {\frac{{12}}{{10}}} \right)\,\,\,\, \to \,\,\,\,\,\boxed{\frac{{5\,\,{\text{cans}}}}{{1\,\,{\text{s}}}}}\,\,\,\frac{{12}}{{10}}\,\,\,\,\,\, \to \,\,\,\,\,\frac{{6\,\,\,{\text{cans}}}}{{1\,\,\,{\text{s}}}}$$

$$? = 600\,\,{\text{cans}}\,\,\,\left( {\frac{{1\,\,s}}{{6\,\,{\text{cans}}}}\,\,\begin{array}{*{20}{c}} \nearrow \\ \nearrow \end{array}} \right)\,\,\, = \,\,\,100\,\,{\text{s}}$$

Obs.: arrows indicate licit converters.

The above follows the notations and rationale taught in the GMATH method.
_________________
Fabio Skilnik :: GMATH method creator (Math for the GMAT)
Our high-level "quant" preparation starts here: https://gmath.net
GMAT Club Legend
Joined: 12 Sep 2015
Posts: 4009
Re: If all machines in a factory are equally efficient and 10 machines  [#permalink]

### Show Tags

31 Aug 2018, 10:00
1
Top Contributor
rohan2345 wrote:
If all machines in a factory are equally efficient and 10 machines take 8 seconds to produce 40 cans, how long will it take 12 machines to produce 600 cans?

A- 25 seconds
B- 50 seconds
C- 1 minute and 40 seconds
D- 2 minutes
E- 3 minutes and 20 seconds

We can also use some number sense to get to the correct answer...

GIVEN: 10 machines take 8 seconds to produce 40 cans
So, 10 machines take 1 second to produce 5 cans (if we divide the work time by 8, then the output is also divided by 8)
So, 1 machines take 1 second to produce 0.5 cans (if we divide the number of machines by 10, then the output is also divided by 10)
So, 12 machines take 1 second to produce 6 cans (if we multiply the number of machines by 12, then the output is also multiplied by 12)

We now know that 12 machines take 1 second to produce 6 cans
We want the 12 machines to make 600 cans.
600/6 = 100
So, 12 machines take 100 seconds to produce 600 cans

100 seconds = 1 minute and 40 seconds.

_________________
Test confidently with gmatprepnow.com
Target Test Prep Representative
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 8109
Location: United States (CA)
Re: If all machines in a factory are equally efficient and 10 machines  [#permalink]

### Show Tags

27 Sep 2019, 08:49
1
rohan2345 wrote:
If all machines in a factory are equally efficient and 10 machines take 8 seconds to produce 40 cans, how long will it take 12 machines to produce 600 cans?

A- 25 seconds
B- 50 seconds
C- 1 minute and 40 seconds
D- 2 minutes
E- 3 minutes and 20 seconds

Since the rate of 10 machines is 40/8 = 5, the rate for 1 machine is 5/10 = 1/2 and the rate for 12 machines is 1/2 x 12 = 6.

Thus, it takes 12 machines 600/6 = 100 seconds = 1 minute 40 seconds to produce 600 cans.

_________________

# Scott Woodbury-Stewart

Founder and CEO

Scott@TargetTestPrep.com
122 Reviews

5-star rated online GMAT quant
self study course

See why Target Test Prep is the top rated GMAT quant course on GMAT Club. Read Our Reviews

If you find one of my posts helpful, please take a moment to click on the "Kudos" button.

e-GMAT Representative
Joined: 04 Jan 2015
Posts: 3074
Re: If all machines in a factory are equally efficient and 10 machines  [#permalink]

### Show Tags

30 Sep 2019, 07:20

Solution

Given
• All machines of a factory are equally efficient.
• 10 machines take 8 seconds to produce 40 cans.

To find
• Time taken by 12 machines to fill 600 cans.

Approach and Working out

10 Machines take 8 seconds to fill 40 cans.
• So, each machine is working 8 seconds. And total 80 seconds.
o So, if 1 machine had been working then it would take 80 seconds to fill 40 cans.
 80 seconds to fill 40 cans.
 So, 1 machine will take 2 seconds to fill 1 can.
• So, 12 machines in 2 seconds can fill 12 cans.
o 12 cans -> 2 seconds
o 12 * 50 cans = 600 cans -> 2 * 50 =100 seconds= 1 min 40 sec

Thus, option C is the correct answer.

_________________
Re: If all machines in a factory are equally efficient and 10 machines   [#permalink] 30 Sep 2019, 07:20
Display posts from previous: Sort by