Last visit was: 24 Jul 2024, 06:10 It is currently 24 Jul 2024, 06:10
Toolkit
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
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

# Sofia runs a business delivering boxes of frequently used household su

SORT BY:
Tags:
Show Tags
Hide Tags
Math Expert
Joined: 02 Sep 2009
Posts: 94605
Own Kudos [?]: 643514 [11]
Given Kudos: 86734
Manager
Joined: 29 May 2017
Posts: 154
Own Kudos [?]: 20 [0]
Given Kudos: 63
Location: Pakistan
Concentration: Social Entrepreneurship, Sustainability
GMAT Club Legend
Joined: 03 Oct 2013
Affiliations: CrackVerbal
Posts: 4915
Own Kudos [?]: 7817 [2]
Given Kudos: 221
Location: India
Manager
Joined: 29 May 2017
Posts: 154
Own Kudos [?]: 20 [0]
Given Kudos: 63
Location: Pakistan
Concentration: Social Entrepreneurship, Sustainability
Re: Sofia runs a business delivering boxes of frequently used household su [#permalink]
ArvindCrackVerbal wrote:
Assuming simple values is probably the fastest and the best method in solving this question.

Let’s assume that Sofia used to deliver 100 boxes a month before the workflow manager was hired. Let’s also say that she worked a total of 10 hours to do this work. Her productivity would then be 10 boxes per hour.

Once the workflow manager was hired, Sofia delivered 20 percent more boxes. This means that she’s now able to deliver 120 boxes. At the same time, she worked 20 percent fewer hours to get this work done which means she worked a total of 8 hours. Her productivity would now be 15 boxes per hour (120 boxes/8 hours).

From 10 boxes/hour to 15 boxes/hour, we see that the increase in Sofia's productivity is 50%. The correct answer option is B.

Hope that helps!

hi...i chose 40 hr per week...and didnt get the answer....can you look at my solution and tell me where i went wrong?
GMAT Club Legend
Joined: 03 Oct 2013
Affiliations: CrackVerbal
Posts: 4915
Own Kudos [?]: 7817 [1]
Given Kudos: 221
Location: India
Re: Sofia runs a business delivering boxes of frequently used household su [#permalink]
1
Kudos
Mansoor50 wrote:
ArvindCrackVerbal wrote:
Assuming simple values is probably the fastest and the best method in solving this question.

Let’s assume that Sofia used to deliver 100 boxes a month before the workflow manager was hired. Let’s also say that she worked a total of 10 hours to do this work. Her productivity would then be 10 boxes per hour.

Once the workflow manager was hired, Sofia delivered 20 percent more boxes. This means that she’s now able to deliver 120 boxes. At the same time, she worked 20 percent fewer hours to get this work done which means she worked a total of 8 hours. Her productivity would now be 15 boxes per hour (120 boxes/8 hours).

From 10 boxes/hour to 15 boxes/hour, we see that the increase in Sofia's productivity is 50%. The correct answer option is B.

Hope that helps!

hi...i chose 40 hr per week...and didnt get the answer....can you look at my solution and tell me where i went wrong?

Hello Mansoor,

You have brought in too many values while trying to solve the question. The problem with this is that more variables means more things to keep a tab on. When you have to handle more variables under a time constraint, it's very natural to miss some of them out.

That's exactly what has happened here. You have just found the difference between the two different cases of productivity. But, you have forgotten to compare it with the initial value and that is where the slip up has happened.

Remember, Percentage Increase = $$\frac{Final Value - Initial Value }{ Initial Value}$$ * 100.

You did find out the numerator, but forgot to compare it with the denominator and simplify. Also, you did not simplify 100/160 to 5/8 and 120/128 to 15/16; instead you kept using the same values to find the difference. Under a time constraint, when you feed your brain with bigger numbers, many times it gets overwhelmed and that's when the calculation mistakes crop up. So, remember to simplify fractions to their lowest form as much as you can.

So, here's what you SHOULD HAVE done:

Percentage Increase = (15/16) - (5/8) / (5/8) * 100 = (5/16) / (5/8) * 100 = 1/2 * 100 = 50%.

You faltered at the final step, hard luck! But hey, it was just a minor detail that you overlooked, so it's okay. Your reasoning wasn't faulty.

Hope that helps!
Manager
Joined: 29 May 2017
Posts: 154
Own Kudos [?]: 20 [0]
Given Kudos: 63
Location: Pakistan
Concentration: Social Entrepreneurship, Sustainability
Re: Sofia runs a business delivering boxes of frequently used household su [#permalink]
ArvindCrackVerbal wrote:
Mansoor50 wrote:
ArvindCrackVerbal wrote:
Assuming simple values is probably the fastest and the best method in solving this question.

Let’s assume that Sofia used to deliver 100 boxes a month before the workflow manager was hired. Let’s also say that she worked a total of 10 hours to do this work. Her productivity would then be 10 boxes per hour.

Once the workflow manager was hired, Sofia delivered 20 percent more boxes. This means that she’s now able to deliver 120 boxes. At the same time, she worked 20 percent fewer hours to get this work done which means she worked a total of 8 hours. Her productivity would now be 15 boxes per hour (120 boxes/8 hours).

From 10 boxes/hour to 15 boxes/hour, we see that the increase in Sofia's productivity is 50%. The correct answer option is B.

Hope that helps!

hi...i chose 40 hr per week...and didnt get the answer....can you look at my solution and tell me where i went wrong?

Hello Mansoor,

You have brought in too many values while trying to solve the question. The problem with this is that more variables means more things to keep a tab on. When you have to handle more variables under a time constraint, it's very natural to miss some of them out.

That's exactly what has happened here. You have just found the difference between the two different cases of productivity. But, you have forgotten to compare it with the initial value and that is where the slip up has happened.

Remember, Percentage Increase = $$\frac{Final Value - Initial Value }{ Initial Value}$$ * 100.

You did find out the numerator, but forgot to compare it with the denominator and simplify. Also, you did not simplify 100/160 to 5/8 and 120/128 to 15/16; instead you kept using the same values to find the difference. Under a time constraint, when you feed your brain with bigger numbers, many times it gets overwhelmed and that's when the calculation mistakes crop up. So, remember to simplify fractions to their lowest form as much as you can.

So, here's what you SHOULD HAVE done:

Percentage Increase = (15/16) - (5/8) / (5/8) * 100 = (5/16) / (5/8) * 100 = 1/2 * 100 = 50%.

You faltered at the final step, hard luck! But hey, it was just a minor detail that you overlooked, so it's okay. Your reasoning wasn't faulty.

Hope that helps!

a big thank you!!
its good to know my thought process was correct...means a lot
Intern
Joined: 02 Dec 2017
Posts: 7
Own Kudos [?]: 2 [2]
Given Kudos: 3
Re: Sofia runs a business delivering boxes of frequently used household su [#permalink]
2
Kudos
The way I approached this questions is mentioned below:
Productivity = Total number of boxes delivered per unit time.
so, P1 = n/x
P2 = 1.2n/0.8x
Increase in Productivity = (P2-P1)/P1 = 50%
Manager
Joined: 24 Nov 2019
Posts: 144
Own Kudos [?]: 51 [0]
Given Kudos: 132
GMAT 1: 760 Q51 V41 (Online)
Re: Sofia runs a business delivering boxes of frequently used household su [#permalink]
Assumptions:

earlier: 100 boxes in 100 hours. Productivity =1
Now : 120 boxes in 80 hours. Productivity = 1.5
Change in productivity = 1.5-1 = 0.5
% change = (0.5/1) * 100 = 50%
Non-Human User
Joined: 09 Sep 2013
Posts: 34061
Own Kudos [?]: 853 [0]
Given Kudos: 0
Re: Sofia runs a business delivering boxes of frequently used household su [#permalink]
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: Sofia runs a business delivering boxes of frequently used household su [#permalink]
Moderator:
Math Expert
94605 posts