SOLUTION: Darla can was and detail 3 cars in 2 hours. Larry can wash and detail the same 3 cars in 1.5 hours. About how long will it take to wash and detail the 3 cars if Darla and Larry wor

Algebra ->  Equations -> SOLUTION: Darla can was and detail 3 cars in 2 hours. Larry can wash and detail the same 3 cars in 1.5 hours. About how long will it take to wash and detail the 3 cars if Darla and Larry wor      Log On


   

Question 119332: Darla can was and detail 3 cars in 2 hours. Larry can wash and detail the same 3 cars in 1.5 hours. About how long will it take to wash and detail the 3 cars if Darla and Larry worked together?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Washing and detailing the 3 cars can be considered 1 job, since that
is all the problem is interested in.
(1 job / 2 hrs) + (1 job / 1.5 hrs) = 1 job / k hrs
1%2F2+%2B+1%2F1.5+=+1+%2F+k
multiply both sides by 3
1.5+%2B+2+=+3%2Fk
3.5+=+3%2Fk
k+=+3%2F3.5
k+=+.857hrs
.857%2A60+=+51.42
Working together, they can do the job in 51 min 25 sec approximately