SOLUTION: if jon can paint a fence in 3 hours and karen can paint it in 6 hours , find how long it takes them to paint it together.

Click here to see ALL problems on Rate-of-work-word-problems

Question 887113: if jon can paint a fence in 3 hours and karen can paint it in 6 hours , find how long it takes them to paint it together.
Found 4 solutions by JulietG, MathTherapy, Alan3354, richwmiller:
Answer by JulietG(1812)   (Show Source):
You can put this solution on YOUR website!
3 + 6 = 9 for two fences, or 4.5 hours for 1 fence
If they're both working together to paint the same fence, divide by 2.
4.5 / 2 = 2.25 hours (or 2 hours 15 minutes)

Answer by MathTherapy(10552)   (Show Source):
You can put this solution on YOUR website!

if jon can paint a fence in 3 hours and karen can paint it in 6 hours , find how long it takes them to paint it together.

2T + T = 6 ------ Multiplying by LCD, 6T
3T = 6
T, or time taken by both, working together = , or hours

Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website!
Parallel resistors, parallel flow and parallel work are similar.
---
t = 3*6/(3+6)
t = 2 hours
=================
To explain:
In 1 hour, jon paints 1/3 of the fence and karen paints 1/6
--> each hour, they paint 1/3 + 1/6 together = 1/2 of the fence.
1/2 per hour --> 2 hours to do the job.

Answer by richwmiller(17219)   (Show Source):
You can put this solution on YOUR website!
You have three solutions (2 correct and 1 incorrect)
jon does 1/3 each hour and karen does 1/6 each hours
1/3+1/6=
common denominator
2/6+1/6=
3/6=
1/2
Each hour they do 1/2 of the job.
t/3+t/6 =1 job
2t/6+t/6=1
3t/6=1
t/2=1
t=2
or
1/3+1/6=1/t
1/2 =1/t
2/6+1/6=1/t
3/6=1/t
1/2 =1/t
t=2