Tommy can paint a fence in 10 hours. If his friend huck helps, they can paint the fence in one hour. How fast would it take huck to paint the fence by himself?

Question

saifoo.khan · Answer

I think there is a mistake here.

saifoo.khan · Answer

1/10 + 1/x = 1

Solve for x.

anonymous · Answer

hmm... this is depressing, I still cant figure it out...

saifoo.khan · Answer

$$\frac{1}{10}+\frac 1x = \frac 11$$

anonymous · Answer

Since Tommy alone can paint the full fence in 10 hours
It means that in 1 hour Tommy can paint 1/10 of the fence

Since Tommy and Huck together finish the work together in 1 hour

=> Huck can finish 9/10 of the fence in 1 hour (because 1/10 is done by Tommy)

So if Huck can finish 9/10 of fence in one hour ,       
then he can finish the full fence in time
          1              1        10           10
= -------  = ---- * ----- = ----- hours
          9               1          9            9
      -----
         10