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

 It is currently 19 Sep 2018, 08:02

### 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

# Nine identical machines, each working at the same constant rate, can

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 49251
Nine identical machines, each working at the same constant rate, can  [#permalink]

### Show Tags

03 Jul 2018, 00:04
00:00

Difficulty:

5% (low)

Question Stats:

94% (01:28) correct 6% (02:28) wrong based on 53 sessions

### HideShow timer Statistics

Nine identical machines, each working at the same constant rate, can stitch 27 jerseys in 4 minutes. How many minutes would it take 4 such machines to stitch 60 jerseys?

(A) 8
(B) 12
(C) 16
(D) 18
(E) 20

_________________
Manager
Joined: 14 Jun 2018
Posts: 57
Re: Nine identical machines, each working at the same constant rate, can  [#permalink]

### Show Tags

03 Jul 2018, 02:26
1
9 machine stitches 27 jersey in 4 minutes
1 machines stitches 1 jersey in (4 * 9)/ 27 minutes. = 4/3
4 machines stitches 60 jersey in (4*60)/3*4 = 20 minutes
Option E
Director
Joined: 20 Feb 2015
Posts: 728
Concentration: Strategy, General Management
Re: Nine identical machines, each working at the same constant rate, can  [#permalink]

### Show Tags

03 Jul 2018, 03:31
Bunuel wrote:
Nine identical machines, each working at the same constant rate, can stitch 27 jerseys in 4 minutes. How many minutes would it take 4 such machines to stitch 60 jerseys?

(A) 8
(B) 12
(C) 16
(D) 18
(E) 20

Using M1D1H1/W1=M2D2H2/W2
W1=27
W2=60

9*4/27=4*m*/60
9*60=m*27=20 minutes
Senior SC Moderator
Joined: 22 May 2016
Posts: 1973
Nine identical machines, each working at the same constant rate, can  [#permalink]

### Show Tags

03 Jul 2018, 13:10
Bunuel wrote:
Nine identical machines, each working at the same constant rate, can stitch 27 jerseys in 4 minutes. How many minutes would it take 4 such machines to stitch 60 jerseys?

(A) 8
(B) 12
(C) 16
(D) 18
(E) 20

If you like R*T=W, one method is to add (# of machines) to LHS

Scenario # 1: Find rate of one machine
$$9$$ machines need $$4$$ minutes to make $$27$$ jerseys
Rate of one machine in $$\frac{jerseys}{minutes}$$?
(# of machines) * R * T = W
$$(9) * R * (4) = 27$$
$$R* 36 = 27$$
$$R=\frac{27}{36}=\frac{3}{4}$$

At that rate, how many minutes do 4 such machines require to stitch 60 jerseys?

Scenario # 2 - Find time
4 machines must sew 60 jerseys at rate of $$\frac{3}{4}$$
Time needed?
(# of machines) * R * T = W
$$(4)*(\frac{3}{4})*T=60$$
$$T*3=60$$
$$T=20$$ minutes

_________________

In the depths of winter, I finally learned
that within me there lay an invincible summer.

Nine identical machines, each working at the same constant rate, can &nbs [#permalink] 03 Jul 2018, 13:10
Display posts from previous: Sort by

# Events & Promotions

 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®.