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

 It is currently 15 Oct 2018, 01:42

### 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

# Working at their respective, constant rates, Leslie can paint a fence

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 49964
Working at their respective, constant rates, Leslie can paint a fence  [#permalink]

### Show Tags

13 Apr 2018, 03:28
00:00

Difficulty:

5% (low)

Question Stats:

87% (00:44) correct 13% (00:34) wrong based on 65 sessions

### HideShow timer Statistics

Working at their respective, constant rates, Leslie can paint a fence in 2 hours and Darryl can paint the same fence in 4 hours. If they work together, how long will it take Leslie and Darryl to paint the fence?

A. 45 minutes
B. 1 hour, 20 minutes
C. 2 hours, 15 minutes
D. 3 hours
E. 6 hours

_________________
Manager
Joined: 30 May 2017
Posts: 120
Location: United States
Schools: HBS '21
GMAT 1: 690 Q50 V32
GRE 1: Q168 V164
GPA: 3.57
Working at their respective, constant rates, Leslie can paint a fence  [#permalink]

### Show Tags

13 Apr 2018, 04:35
Bunuel wrote:
Working at their respective, constant rates, Leslie can paint a fence in 2 hours and Darryl can paint the same fence in 4 hours. If they work together, how long will it take Leslie and Darryl to paint the fence?

A. 45 minutes
B. 1 hour, 20 minutes
C. 2 hours, 15 minutes
D. 3 hours
E. 6 hours

The solution is as follows.

1/2 + 1/4 = 1/x where x is the number of hours it takes Leslie and Darryl to paint the fence

3/4 = 1/x

4/3 = x . Therefore x = 4/3 hours = 1 hour, 20 minutes.

Hence option B. 1 hour, 20 minutes is the answer.

Give me +1 Kudos if you like the explanation. Thanks.
_________________

Kindly press the +1Kudos if you like the explanation. Thanks a lot!!!

Director
Joined: 02 Oct 2017
Posts: 643
Re: Working at their respective, constant rates, Leslie can paint a fence  [#permalink]

### Show Tags

28 Apr 2018, 19:12
When want to calculate work done by by two when individual work done is given then

(A*B)/A+B
=8/6 hr
=8*60/6 min
=80 min

i.e. 1 hr 20 minutes

Posted from my mobile device
_________________

Give kudos if you like the post

Manager
Joined: 22 Jun 2017
Posts: 72
Location: Brazil
GMAT 1: 600 Q48 V25
GPA: 3.5
WE: Engineering (Energy and Utilities)
Re: Working at their respective, constant rates, Leslie can paint a fence  [#permalink]

### Show Tags

28 Apr 2018, 19:39
Option B

Work = Rate * Time

Leslie rate: $$\frac{1}{2}$$

Darryl rate: $$\frac{1}{4}$$

Leslie + Darryl rate: $$\frac{1}{2}$$ + $$\frac{1}{4}$$ = $$\frac{3}{4}$$

Work = Rate * Time

1 = $$\frac{3}{4}$$ * Time

Time = $$\frac{4}{3}$$ hour = 1 hour, 20 minutes
Re: Working at their respective, constant rates, Leslie can paint a fence &nbs [#permalink] 28 Apr 2018, 19:39
Display posts from previous: Sort by