SOLUTION: tom can paint a fence in 8 hours. Huck can paint the same fence in 5 hours. How long would it take to put two coats of paint on the fence if Tom and Huck work together?

Algebra ->  Rate-of-work-word-problems -> SOLUTION: tom can paint a fence in 8 hours. Huck can paint the same fence in 5 hours. How long would it take to put two coats of paint on the fence if Tom and Huck work together?      Log On


   

Question 794705: tom can paint a fence in 8 hours. Huck can paint the same fence in 5 hours. How long would it take to put two coats of paint on the fence if Tom and Huck work together?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Another way to say 2 coats is
to paint the fence twice
Also, that is the same as painting
2 identical fences
---------------
Tom's rate is:
+1%2F8+ = ( 1 fence ) / ( 8 hrs )
Huck's rate is:
+1%2F5+ = ( 1 fence ) / ( 5 hrs )
---------------------------
Let +t+ = the time in hrs for them
to paint 2 fences
+2%2Ft+ = ( 2 fences ) / ( t hrs )
---------------------------
+1%2F8+%2B+1%2F5+=+2%2Ft+
Multiply both sides by +40t+
+5t+%2B+8t+=+80+
+13t+=+80+
+t+=+6.154+
It will take them 6.154 hrs