SOLUTION: two welders working together can complete a job in 6 hrs. one of the welders, working alone, can complete the task in 10 hrs. how long would it take the second welder, working alon

Algebra ->  Rate-of-work-word-problems -> SOLUTION: two welders working together can complete a job in 6 hrs. one of the welders, working alone, can complete the task in 10 hrs. how long would it take the second welder, working alon      Log On


   

Question 847754: two welders working together can complete a job in 6 hrs. one of the welders, working alone, can complete the task in 10 hrs. how long would it take the second welder, working alone, to complete the task
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +t+ = time in hours for the 2nd
welder to do the job alone
-----------------------
1st welder's rate of working:
( 1 job ) / ( 10 hrs )
Their rate of working together:
( 1 job ) / ( 6 hrs )
-------------------------
Add their individual rates of working
to get their rate working to gether:
+1%2F10+%2B+1%2Ft+=+1%2F6+
Multiply both sides by +30t+
+3t+%2B+30+=+5t+
+2t+=+30+
+t+=+15+
15 hours is the time for the 2nd
welder to do the job alone
check:
+1%2F10+%2B+1%2Ft+=+1%2F6+
+1%2F10+%2B+1%2F15+=+1%2F6+
+3%2F30+%2B+2%2F30+=+5%2F30+
+5%2F30+=+5%2F30+
OK