SOLUTION: Karma and Tshering are washing a pile of clothes. When they wash separately, Karma can finish it in 4 hours and Tshering in 6 hours. They work together for 2 hours and then Karma l

Algebra ->  Rate-of-work-word-problems -> SOLUTION: Karma and Tshering are washing a pile of clothes. When they wash separately, Karma can finish it in 4 hours and Tshering in 6 hours. They work together for 2 hours and then Karma l      Log On


   

Question 888094: Karma and Tshering are washing a pile of clothes. When they wash separately, Karma can finish it in 4 hours and Tshering in 6 hours. They work together for 2 hours and then Karma left to attend some other chores. How long will it take for Tshering to finish washing the clothes?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +x+ = the fraction of the pile of clothes
that they can get done working together
Karma's rate of washing:
( 1 pile ) / ( 4 hrs )
Tshering's rate of washing:
( 1 pile ) / ( 6 hrs )
------------------------
Add their rates to get rate working together
+1%2F4+%2B+1%2F6+=+x%2F2+
Multiply both sides by +12+
+3+%2B+2+=+6x+
+6x+=+5+
+x+=+5%2F6+
5/6 of the pile got done when working together
That means 1/6 is left to finish
--------------------------------
Let +t+ = time in hours for Tshering to finish washing
( Tshering's rate ) = ( fraction of pile left / t )
+1%2F6+=+%28%281%2F6%29%29+%2F+t+
+t+=+1+
Tshering will take 1 hr to finish washing clothes