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.

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:

Your wish is my command Laxieqv, here is an especially [#permalink]
01 Nov 2005, 21:24

Your wish is my command Laxieqv, here is an especially "non-understandable" word problem for you!

Two machines are sawing wood but due to space limitations only one of the two machines can operate. Machine A is used for the first shift and the other machine for the second shift, while both work half of the third shift. Machine A can do the job in 12 days if it worked two shifts and Machine B can do the job in 15 days if it worked two shifts. How many days will it take to do the job with the current work schedule?

14
13
11
9
7

I'm going to answer nature's call while I let you blokes solve this one...

_________________

"Wow! Brazil is big." â€”George W. Bush, after being shown a map of Brazil by Brazilian president Luiz Inacio Lula da Silva, Brasilia, Brazil, Nov. 6, 2005

3rd shift, is what is confusing.
if 1/2 of 3rd shift A works and 1/2 B works, it is 80/9 = 9
if only for 1/2 of the shift both work (since both can't work simultaneously - say 1/4 A and 1/4 B) - Ans would be 32/3 = 11

Re: All I do is work work work!!!! (from challenge 6) [#permalink]
01 Nov 2005, 21:44

My old is gold approach:

Working 2 shifts in a day, A can do a job in 12 days.
Working 1.5 shifts in a day, A can do a job in 16 days.

Working 2 shifts in a day, B can do a job in 15 days.
Working 1.5 shifts in a day, B can do a job in 20 days.

Working 1.5 shifts in a day, A and B can do {(1/16)+(1/20)} = 9/80 of a job in 1 day.
Working 1.5 shifts in a day, A and B can do a job in 80/9 = approx 9 days.

A: 1 job in 12 days if work 2 shifts = 1 job in 24 days per shift = 1/24 job per day per shift
B: 1 job in 15 days if work 2 shits = 1 job in 30 days per shift = 1/30 job per day per shift

Machine A works 3/2 shifts per day = 3/2*1/24 = 1/16 of the job per day
Machine B works 3/2 shifts per day = 3/2*1/30 = 1/20 of the job per day

Together, 9/80 job per day, so 1 job will take 80/9 days ~ 9 days

Jeez!!! you guys are like jack rabbits on the only cabbage left in the field.

Nice job guys OA is 9 _________________

"Wow! Brazil is big." â€”George W. Bush, after being shown a map of Brazil by Brazilian president Luiz Inacio Lula da Silva, Brasilia, Brazil, Nov. 6, 2005