SOLUTION: Together, Bob and Tom take 4 hours to get the yard work done. If Bob works alone, it takes him 6 hours. How long would it take Tom, working alone, to do all of the yard work?

Algebra ->  Rate-of-work-word-problems -> SOLUTION: Together, Bob and Tom take 4 hours to get the yard work done. If Bob works alone, it takes him 6 hours. How long would it take Tom, working alone, to do all of the yard work?      Log On


   



Question 457478: Together, Bob and Tom take 4 hours to get the yard work done. If Bob works alone, it takes him 6 hours. How long would it take Tom, working alone, to do all of the yard work?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let t = number of hrs Tom takes to do it
Add their rates of working
( 1 yard ) / ( 6 hrs ) + ( 1 yard ) / ( t hrs ) = ( 1 yard ) / (4 hrs )
+1%2F6+%2B+1%2Ft+=+1%2F4+
Multiply both sides by +12t+
+2t+%2B+12+=+3t+%7D%7D%7B%7D%0D%0A%7B%7B%7B+t+=+12+
It takes Tom 12 hrs working alone