Working together, Jeff and Ashley painted their apartment in 6 hours.

Question

Working together, Jeff and Ashley painted their apartment in 6 hours. If Jeff had been working alone, he could have painted the whole apartment in 10 hours. How many hours would it have taken Ashley to paint the apartment alone?

A. 4
B. 12
C. 15
D. 16
E. 20

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paragw · Answer

https://gmatclub.com/forum/download/file.php?id=86249 Therefore, Efficiency of Ashley = 2 u/h Time taken Ashley to paint the apartment alone = 30/2 = 15h Hence, C GMAT-Club-Forum-8tcixe39.png

ravi1522 · Answer

Hello ,
Working together, Jeff and Ashley painted their apartment in 6 hours. If Jeff had been working alone, he could have painted the whole apartment in 10 hours. How many hours would it have taken Ashley to paint the apartment alone?

so as jeff worked for 6 hours he must have completed 60 % work ,so remaining 40% is completed for Ashley in 6 hours .
for whole work ashley will take 6/0.4= 15 hours

Hence answer is C

sompant_98 · Answer

Jeff and Ashley together worked for 6 hours.
Jeff alone woked for 10 hours, therefore Jeff's one hour work would be 1/10.
Now Jeff and Ashley's one hour work would be equal to 1/6
Therefore, (1/10) +(1/A)=1/6
A= 15 hours

shankk · Answer

C

1/6=1/A+1/10
1/6-1/10=1/A
4/60=1/A
1/15=1/A
A=15hours

Reon · Answer

Working together, Jeff and Ashley painted their apartment in 6 hours. If Jeff had been working alone, he could have painted the whole apartment in 10 hours. How many hours would it have taken Ashley to paint the apartment alone?

Given: (1/J)+(1/A)= 1/6 
Also, Jeff can alone paint whole apartment in 10 hours.

(1/10)+(1/A)=1/6 
1/A = (1/6)-(1/10) =4/60= 1/15 
A= 15 
Ashley can paint the apartment alone in 15 hours.

C

Souradeep17 · Answer

Let total unit of work be 30
jeff+ashley together does in 6 hours. 
per hour work will be 5units
Jeff alone does in 10 hours , per hour work will be 3
Ashley per hour work is 5-3=2 unit 
so time taken will be 30/2=15 hours( option C)

Dereno · Answer

Jeff and Ashley work together for 6 hours.

Ashley worked alone for 10 hours.

Let the total work be LCM of (6,10) = 60 units

Total Efficiency of Jeff and Ashley = work / time = 60/6 = 10 units

Efficiency of Ashley = 60 / 10 = 6 units.

Efficiency of Jeff = (10-6) = 4 units.

Time taken by Jeff working alone = Work / Efficiency = 60/4 =  15 days.

Option C

Working together, Jeff and Ashley painted their apartment in 6 hours.

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Working together, Jeff and Ashley painted their apartment in 6 hours.

Prep Toolkit

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