It is currently 29 Jun 2017, 04:14

### 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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# Jonathan can type a 20 page document in 40 minutes, Susan

Author Message
TAGS:

### Hide Tags

Intern
Joined: 08 Oct 2009
Posts: 8
Jonathan can type a 20 page document in 40 minutes, Susan [#permalink]

### Show Tags

12 Oct 2009, 12:42
1
KUDOS
2
This post was
BOOKMARKED
00:00

Difficulty:

15% (low)

Question Stats:

81% (02:27) correct 19% (02:03) wrong based on 216 sessions

### HideShow timer Statistics

Jonathan can type a 20 page document in 40 minutes, Susan can type it in 30 minutes, and Jack can type it in 24 minutes. Working together, how much time will it take them to type the same document?

A. 5 minutes
B. 10 minutes
C. 15 minutes
D. 18 minutes
E. 20 minutes
[Reveal] Spoiler: OA

Last edited by Bunuel on 09 Feb 2012, 13:58, edited 1 time in total.
Edited the question and added the OA
Math Expert
Joined: 02 Sep 2009
Posts: 39756

### Show Tags

12 Oct 2009, 13:00
1
KUDOS
Expert's post
timmaxwell8 wrote:
30. Jonathan can type a 20 page document in 40 minutes, Susan can type it in 30 minutes, and Jack can type it in 24 minutes. Working together, how much time will it take them to type the same document?

A. 5 minutes
B. 10 minutes
C. 15 minutes
D. 18 minutes
E. 20 minutes

J=20/40=1/2per min
S=20/30=2/3per min
JK=20/24=5/6per min

In one min together 1/2+2/3+5/6=12/6=2 pages.

For 20 pages=20/2=10

B.
_________________
Senior Manager
Joined: 18 Aug 2009
Posts: 423
Schools: UT at Austin, Indiana State University, UC at Berkeley
WE 1: 5.5
WE 2: 5.5
WE 3: 6.0

### Show Tags

12 Oct 2009, 21:13
4
KUDOS
You may set up common equation like this:

job/A+job/B+job/C=job/x
Memorize this universal formula, you will need it definitely for GMAT.

and find x from this equation
In this specific case, the equation will look like this:

20/40+20/30+20/24=20/x
If you solve this equation, you get the same answer D (10)

If you like my post, please give me kudos.
_________________

Never give up,,,

Manager
Joined: 15 Sep 2009
Posts: 134

### Show Tags

13 Oct 2009, 10:23
I will go with option B)10
Manager
Joined: 12 Oct 2009
Posts: 115

### Show Tags

13 Oct 2009, 10:54
Bunuel wrote:
timmaxwell8 wrote:
30. Jonathan can type a 20 page document in 40 minutes, Susan can type it in 30 minutes, and Jack can type it in 24 minutes. Working together, how much time will it take them to type the same document?

A. 5 minutes
B. 10 minutes
C. 15 minutes
D. 18 minutes
E. 20 minutes

J=20/40=1/2per min
S=20/30=2/3per min
JK=20/24=5/6per min

In one min together 1/2+2/3+5/6=12/6=2 pages.

For 20 pages=20/2=10

B.

If the work involved here is to type the 20page document we can even avoid calculating time taken per page.
will this apporach backfire?

Regards
Asterix
"Time is of gr8 essence"
Manager
Joined: 18 Jul 2009
Posts: 169
Location: India
Schools: South Asian B-schools

### Show Tags

13 Oct 2009, 11:14
1/40+1/30+1/24 = 24/240 = 1/10 work per min = 10 min to complete work
_________________

Bhushan S.
If you like my post....Consider it for Kudos

Director
Joined: 01 Apr 2008
Posts: 881
Name: Ronak Amin
Schools: IIM Lucknow (IPMX) - Class of 2014

### Show Tags

17 Oct 2009, 23:32
Formula for time taken by 3 guys is:

t1*t2*t3 / ( t1*t2 + t2*t3 + t3*t1 ) , this might be lead to a faster calculation
Manager
Joined: 25 May 2011
Posts: 152

### Show Tags

29 Oct 2011, 06:42
GMAT Club Legend
Joined: 09 Sep 2013
Posts: 16031
Re: Jonathan can type a 20 page document in 40 minutes, Susan [#permalink]

### Show Tags

21 Oct 2013, 06:44
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
GMAT Club Legend
Joined: 09 Sep 2013
Posts: 16031
Re: Jonathan can type a 20 page document in 40 minutes, Susan [#permalink]

### Show Tags

10 Oct 2016, 07:24
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
Re: Jonathan can type a 20 page document in 40 minutes, Susan   [#permalink] 10 Oct 2016, 07:24
Similar topics Replies Last post
Similar
Topics:
3 If one person can type 10 pages every 5/3 of an hour, to type 252 page 3 01 May 2017, 14:22
16 If 20 typists can type 48 letters in 20 minutes, then how many letters 12 03 Jun 2017, 13:37
24 If two typists can type two pages in two minutes, how many t 14 05 Sep 2016, 12:51
60 Printer a takes 40 more minutes to print the pages of a book 18 06 Jun 2017, 16:01
26 Working together, John and Jack can type 20 pages in one hou 14 31 Aug 2016, 07:31
Display posts from previous: Sort by