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.

It appears that you are browsing the GMAT Club forum unregistered!

Signing up is free, quick, and confidential.
Join other 500,000 members and get the full benefits of GMAT Club

Registration gives you:

Tests

Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.

Applicant Stats

View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more

Books/Downloads

Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

Working together, printer A and printer B would finish the [#permalink]

Show Tags

01 Sep 2010, 11:12

2

This post received KUDOS

22

This post was BOOKMARKED

00:00

A

B

C

D

E

Difficulty:

65% (hard)

Question Stats:

70% (03:18) correct
30% (02:56) wrong based on 497 sessions

HideShow timer Statistics

Working together, printer A and printer B would finish the task in 24 minutes. Printer A alone would finish the task in 60 minutes. How many pages does the task contain if printer B prints 5 pages a minute more than printer A ?

I know this question is relatively symol if make an equation in one vaibale ... I tried to do it by applying the fundamental of A = Jobs per min * time ( the way we typically solve the work problems ) and i was stuck

I did jobs per minute A , 1/60 combined rate = 1/24

so rate of b = 1/24 - 1/60 = 1/40

but could not arrive at the solution ... i tried to form the equation by assuming x as the total numbe of pages So x/60+ x+5/40 = cld nt take ot forward from here kindly see where am I losing the track !

.Working together, printer A and printer B would finish the task in 24 minutes. Printer A alone would finish the task in 60 minutes. How many pages does the task contain if printer B prints 5 pages a minute more than printer A ?

a. 600 b. 800 c. 1000 d. 1200 e. 1500

answer: A I know this question is relatively symol if make an equation in one vaibale ... I tried to do it by applying the fundamental of A = Jobs per min * time ( the way we typically solve the work problems ) and i was stuck

I did jobs per minute A , 1/60 combined rate = 1/24

so rate of b = 1/24 - 1/60 = 1/40

but could not arrive at the solution ... i tried to form the equation by assuming x as the total numbe of pages So x/60+ x+5/40 = cld nt take ot forward from here kindly see where am I losing the track !

Let the rate of printer A be \(a\) pages per minute, the rate of printer B be \(b\) pages per minute and whole task be \(x\) pages.

\(time*rate=job \ done\):

Working together, printer A and printer B would finish the task in 24 minutes" --> \(24(a+b)=x\); Printer A alone would finish the task in 60 minutes --> \(60a=x\); Printer B prints 5 pages a minute more than printer A --> \(b=a+5\).

.Working together, printer A and printer B would finish the task in 24 minutes. Printer A alone would finish the task in 60 minutes. How many pages does the task contain if printer B prints 5 pages a minute more than printer A ?

a. 600 b. 800 c. 1000 d. 1200 e. 1500

answer: A I know this question is relatively symol if make an equation in one vaibale ... I tried to do it by applying the fundamental of A = Jobs per min * time ( the way we typically solve the work problems ) and i was stuck

I did jobs per minute A , 1/60 combined rate = 1/24

so rate of b = 1/24 - 1/60 = 1/40

but could not arrive at the solution ... i tried to form the equation by assuming x as the total numbe of pages So x/60+ x+5/40 = cld nt take ot forward from here kindly see where am I losing the track !

Let the rate of printer A be \(a\) pages per minute, the rate of printer B be \(b\) pages per minute and whole task be \(x\) pages.

\(time*rate=job \ done\):

Working together, printer A and printer B would finish the task in 24 minutes" --> \(24(a+b)=x\); Printer A alone would finish the task in 60 minutes --> \(60a=x\); Printer B prints 5 pages a minute more than printer A --> \(b=a+5\).

.Working together, printer A and printer B would finish the task in 24 minutes. Printer A alone would finish the task in 60 minutes. How many pages does the task contain if printer B prints 5 pages a minute more than printer A ?

a. 600 b. 800 c. 1000 d. 1200 e. 1500

answer: A I know this question is relatively symol if make an equation in one vaibale ... I tried to do it by applying the fundamental of A = Jobs per min * time ( the way we typically solve the work problems ) and i was stuck

I did jobs per minute A , 1/60 combined rate = 1/24

so rate of b = 1/24 - 1/60 = 1/40

but could not arrive at the solution ... i tried to form the equation by assuming x as the total numbe of pages So x/60+ x+5/40 = cld nt take ot forward from here kindly see where am I losing the track !

Let the rate of printer A be \(a\) pages per minute, the rate of printer B be \(b\) pages per minute and whole task be \(x\) pages.

\(time*rate=job \ done\):

Working together, printer A and printer B would finish the task in 24 minutes" --> \(24(a+b)=x\); Printer A alone would finish the task in 60 minutes --> \(60a=x\); Printer B prints 5 pages a minute more than printer A --> \(b=a+5\).

I have always one confusion in rate and work problems can you please clarify this?,

When do we add rates i.e what you did above...... \(24(a+b)=x\);

and when do we divide by rates i.e something . rate =(Job done/ time)

Regards

Srinath

You can denote rate directly by some variable (a in the solution) or express rate as a reciprocal of time. For example, say printer A needs t minutes to print 1 page and printer B needs m minutes to print 1 page, then the rate of printer A would be job/time=1/t pages per minute and the rate of printer B would be 1/m pages per minute (rate is a reciprocal of time, so 1/t=a and 1/m=b). In this case the equation would be 24(1/t+1/m)=x.

Re: Working together, printer A and printer B would finish the [#permalink]

Show Tags

08 Sep 2012, 05:51

First thing i did was i found out time that is required to B to complete the task alone: 1/24-1/60=3/120=1/40. Then i looked at the information which states that the rate of B is 5+ page than that of A so, lets say x is the number of pages printed by A per minute, so the task consists of 60*x or 40*(x+5) pages. I can make an equation: 60x=40(x+5), 20x=200, x=10, total number of pages is 60*10=600 or 40*15=600

Answer is A.

It is clear but it took me about 3 min to do it, does it because i am doing it slow or i am using longer route? _________________

If you found my post useful and/or interesting - you are welcome to give kudos!

Re: Working together, printer A and printer B would finish the [#permalink]

Show Tags

04 Mar 2013, 00:40

1

This post received KUDOS

gauravnagpal wrote:

Working together, printer A and printer B would finish the task in 24 minutes. Printer A alone would finish the task in 60 minutes. How many pages does the task contain if printer B prints 5 pages a minute more than printer A ?

I know this question is relatively symol if make an equation in one vaibale ... I tried to do it by applying the fundamental of A = Jobs per min * time ( the way we typically solve the work problems ) and i was stuck

I did jobs per minute A , 1/60 combined rate = 1/24

so rate of b = 1/24 - 1/60 = 1/40

but could not arrive at the solution ... i tried to form the equation by assuming x as the total numbe of pages So x/60+ x+5/40 = cld nt take ot forward from here kindly see where am I losing the track !

total time taken by B = 24 * 60 / (60 -24) = 40 min.

A take 60 min. B takes 40 min to complete a task.

Now, divide the values given in option (in Ans) to get the rate per min.

option A: 600 / 10 = 60 & 600/40 = 15...> this satisfies the condition given in question stem that printer B prints 5 pages a minute more than printer A ? . therefore A _________________

Re: Working together, printer A and printer B would finish the [#permalink]

Show Tags

21 Sep 2013, 11:31

1

This post received KUDOS

1

This post was BOOKMARKED

Ta = 60min Ra = 1/Ta = 1/60 Rb = 1/Tb

Combined task completion time 24min. =Ra + Rb =1/60 + 1/Tb = 1/24 Tb = 40 min.

Ra = X/Ta Rb = X/Tb

Ra + 5 = Rb X/Ta + 5 = X/Tb X/60 + 5 = X/40 X=600 Ans. _________________

Piyush K ----------------------- Our greatest weakness lies in giving up. The most certain way to succeed is to try just one more time. ― Thomas A. Edison Don't forget to press--> Kudos My Articles: 1. WOULD: when to use?| 2. All GMATPrep RCs (New) Tip: Before exam a week earlier don't forget to exhaust all gmatprep problems specially for "sentence correction".

.Working together, printer A and printer B would finish the task in 24 minutes. Printer A alone would finish the task in 60 minutes. How many pages does the task contain if printer B prints 5 pages a minute more than printer A ?

a. 600 b. 800 c. 1000 d. 1200 e. 1500

answer: A I know this question is relatively symol if make an equation in one vaibale ... I tried to do it by applying the fundamental of A = Jobs per min * time ( the way we typically solve the work problems ) and i was stuck

I did jobs per minute A , 1/60 combined rate = 1/24

so rate of b = 1/24 - 1/60 = 1/40

but could not arrive at the solution ... i tried to form the equation by assuming x as the total numbe of pages So x/60+ x+5/40 = cld nt take ot forward from here kindly see where am I losing the track !

Let the rate of printer A be \(a\) pages per minute, the rate of printer B be \(b\) pages per minute and whole task be \(x\) pages.

\(time*rate=job \ done\):

Working together, printer A and printer B would finish the task in 24 minutes" --> \(24(a+b)=x\); Printer A alone would finish the task in 60 minutes --> \(60a=x\); Printer B prints 5 pages a minute more than printer A --> \(b=a+5\).

I'm curious about the 1/a+1/b=1/24 solution as well. I started out trying that way and got stuck at the same point as the other fellow. Is there any way to solve it once you have 1/60+1/40 for their combined rates? Or is that just a dead end?

edit: Also, question #2:

Shouldn't the equation be 24(1/a+1/b)=x; ? Since you have 24 minutes in which the machines are working at their individual rates, doing 1/a and 1/b of the job per minute? I don't get how one can know when to arbitrarily use "a" instead of '1/a" or "b" instead of "1/b"

.Working together, printer A and printer B would finish the task in 24 minutes. Printer A alone would finish the task in 60 minutes. How many pages does the task contain if printer B prints 5 pages a minute more than printer A ?

a. 600 b. 800 c. 1000 d. 1200 e. 1500

answer: A I know this question is relatively symol if make an equation in one vaibale ... I tried to do it by applying the fundamental of A = Jobs per min * time ( the way we typically solve the work problems ) and i was stuck

I did jobs per minute A , 1/60 combined rate = 1/24

so rate of b = 1/24 - 1/60 = 1/40

but could not arrive at the solution ... i tried to form the equation by assuming x as the total numbe of pages So x/60+ x+5/40 = cld nt take ot forward from here kindly see where am I losing the track !

Let the rate of printer A be \(a\) pages per minute, the rate of printer B be \(b\) pages per minute and whole task be \(x\) pages.

\(time*rate=job \ done\):

Working together, printer A and printer B would finish the task in 24 minutes" --> \(24(a+b)=x\); Printer A alone would finish the task in 60 minutes --> \(60a=x\); Printer B prints 5 pages a minute more than printer A --> \(b=a+5\).

I'm curious about the 1/a+1/b=1/24 solution as well. I started out trying that way and got stuck at the same point as the other fellow. Is there any way to solve it once you have 1/60+1/40 for their combined rates? Or is that just a dead end?

edit: Also, question #2:

Shouldn't the equation be 24(1/a+1/b)=x; ? Since you have 24 minutes in which the machines are working at their individual rates, doing 1/a and 1/b of the job per minute? I don't get how one can know when to arbitrarily use "a" instead of '1/a" or "b" instead of "1/b"

In this case we'd have: The rate of printer A = 1/a pages per minute, where a is the time to print 1 page. The rate of printer B = 1/b pages per minute, where b is the time to print 1 page.

Working together, printer A and printer B would finish the task in 24 minutes" --> \(24(\frac{1}{a}+\frac{1}{b})=x\); Printer A alone would finish the task in 60 minutes --> \(60*\frac{1}{a}=x\); Printer B prints 5 pages a minute more than printer A --> \(\frac{1}{b}=\frac{1}{a}+5\).

Re: Working together, printer A and printer B would finish the [#permalink]

Show Tags

18 Mar 2014, 07:00

2

This post received KUDOS

1

This post was BOOKMARKED

Rate A= X Rate B= X+5

Work(A)=> X * 60 = 60X

Rate(A+B) * 24 = Work

(2X+5) * 24 = 60X

X=10 _________________

Rgds, TGC! _____________________________________________________________________ I Assisted You => KUDOS Please _____________________________________________________________________________

Re: Working together, printer A and printer B would finish the [#permalink]

Show Tags

15 May 2014, 11:02

2

This post received KUDOS

2

This post was BOOKMARKED

Easiest way to do this: Machine A and B can do the task in 24 minutes thus Rate of A and B = 1/24. Now given A can do the task in 60 minutes therefore Rate of A= 1/60. We know that Rate of A and B = Rate of A + Rate of B therefore Rate of B= Rate of A and B - Rate of A = 1/24-1/60= 1/40. Now we know that Rate of B = 1/40 thus B can do the work in 40 minutes.

Let pages printed per minute by A = x, given that pages printed by B per minute is 5 more than that of A Pages printed by B per minute = x+5 Now Complete task is done by A in 60 minutes therefore total number of pages printed by A = x * 60 Also Complete task is done by B in 40 minutes therefore total number of pages printed by B = (x+5) * 40 therefore x * 60 = (x+5) * 40 therefore x=10 thus the total number of pages in task = x*60 = 10*60 = 600

Re: Working together, printer A and printer B would finish the [#permalink]

Show Tags

18 May 2015, 10:55

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: Working together, printer A and printer B would finish the [#permalink]

Show Tags

13 Jun 2016, 01:49

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. _________________

Part 2 of the GMAT: How I tackled the GMAT and improved a disappointing score Apologies for the month gap. I went on vacation and had to finish up a...

Cal Newport is a computer science professor at GeorgeTown University, author, blogger and is obsessed with productivity. He writes on this topic in his popular Study Hacks blog. I was...

So the last couple of weeks have seen a flurry of discussion in our MBA class Whatsapp group around Brexit, the referendum and currency exchange. Most of us believed...