SOLUTION: It takes 1 person 2 hours to paint a car. It takes another person 4 hours to paint a car. Another person also takes 4 hours to paint a car.How long will it take all of them to pai

Algebra ->  Rate-of-work-word-problems -> SOLUTION: It takes 1 person 2 hours to paint a car. It takes another person 4 hours to paint a car. Another person also takes 4 hours to paint a car.How long will it take all of them to pai      Log On


   



Question 774362: It takes 1 person 2 hours to paint a car. It takes another person 4 hours to paint
a car. Another person also takes 4 hours to paint a car.How long will it take all of them to paint 1 car.

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
t takes 1 person 2 hours to paint a car.
It takes another person 4 hours to paint a car.
Another person also takes 4 hours to paint a car.
How long will it take all of them to paint 1 car.
:
Let t = time for all three to paint the car
Let the completed job = 1
:
Each will do a fraction of the job, the three factions add up to 1
t%2F2 + t%2F4 + t%2F4 = 1
multiply by 4 to clear the denominators, resulting in:
2t + t + t = 4
4t = 4
t = 1 hr for all three to do the job