SOLUTION: Please help me with this question!
It takes you 9 mins to wash a car and it takes your friend 12 mins to wash a car. How long does it take the two of you to wash 7 cars if you
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It takes you 9 mins to wash a car and it takes your friend 12 mins to wash a car. How long does it take the two of you to wash 7 cars if you
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Question 342784: Please help me with this question!
It takes you 9 mins to wash a car and it takes your friend 12 mins to wash a car. How long does it take the two of you to wash 7 cars if you work together? Answer by mananth(16946) (Show Source):
You can put this solution on YOUR website! I take 9 minutes
so 1/9 of the job I do in 1 minute
..
my friend takes 12 minutes
he tdoes 1/12 of the job in 1 minute
..
Together they can do 1/9+1/12 of the job in 1 minute
LCD 36
(4+3)/36
7/36 of the job they do in 1 minute
so they take 36/7 minutes to clean the car together
5.14 hours
7 cars they take 7*5.14 = 35.98 minutes
